Earth Dams (USDA, Technical)

GATED OUTLET APPURTENANCES EARTH DAMS

TECHNICAL RELEASE NO.

-

-

-- -

-

-

-

--

-

-

UNITED STATES DEPARTMENT of AGRICULTURE SOIL CONSERVATION SERVICE ENGINEERING DMSION

UNITED STATES DEPARTMENT OF AGRICULTURE SOIL CONSERVATION SERVICE Regional Technical Service Center Engineering & Watershed Planning Unit Portland, Oregon

This manual has been prepared to assist the design engineer in development of plans for gated outlet appurtenances associated with small earth dams.

The original and resourceful charts provide

both ready solution to design and show the full range of compatible alternatives in related design details. The basic design phtlosophy, criteria and procedure are presented in the accompanying narrative. Judicious use of both design charts and standard construction details will offer opportunity for a marked improvement in the quality of most plans and an equally significant reduction in time required for their preparation. Harry W. Firman, Design Engineer, is responsible for the concepts and content of this manual. chapter, Hydraulic Controls.

Robert Morland prepared the

Valuable counsel and assistance were

provided by Frank Muceus, Design Section Head, and other staff members.

June 1969

TABLE OF CONTENTS

FRONTISPIECE Section A

-

INTRODUCTION

B

-

HYDRAULICS

C

-

INLET STRUCTURE

D

-

CONTROLS

E

-

CONDUITS

F

-

OUTLET STRUCTURES

G

-

MISCELLANEOUS STRUCTURES

H

-

DRAWING LAYOUT AND SUMMARY

I

-

BIBLIOGRAPHY

J

- APPENDIX

SECTION A

-

INTRODUCTION

Contents

General

...........................

Page A- 1

Figures

................ ...................

A-1 Standard-Equivalent Dam

A- 3

A-2

A- 5

Procedure Flowchart

SECTION A

-

INTRODUCTION

This design manual contains procedure, design aids, standard details and drawings, useful for developing construction drawings for gated outlets and appurtenances common to earth dams used for storage of water Tor irrigation. As the cover graphically indicates, the planner needs only the basic data to enter this guide and come out with essentially the completed drawings for the outlet appurtenances. Design aids in the form of nomographs, charts and tables have been developed wherever possible to provide ready solution of design analyses Examples have been placed on each of the more complex charts and nomographs to facilitate their use and help the designer grasp the relationship between dependent variables in identifying most alternatives. Some of the figures may appear complicated and require some study of the example to understand the relationships expressed. Once vaster of a chart, the designer has a comprehensive understanding and perspective of the relationship between elements attainable in no other way. Each section of the manual is presented in adequate detail for treatment of its specific subject in design of small irrigation storage structures. An example is continued through the manual. As each section is finished, the progressive example is completed to include the system components discussed in that section. The hydraulics section is a general treatment of hydraulic design of gated outlet systems. It is in adequate detail for preliminary design purposes and in many cases satisfactory for final design. Refined analysis is recommended where critical design factors and cost alternatives are involved. Discussion of hydraulic systems for operation of control gates on earth dam conduits is presented in detail since the application is somewhat unique. The hydraulic system offers advantages under certain conditions over the mechanical gate stem control that makes it worth consideration. The importance of proper conduit design and installation cannot be overstressed to insure safety of the structure. It is usually impractical if not impossible to repair deficiencies in conduits through embankments; this unit of the system must be done right the first time. Every item presented in this section deserves careful consideration. Outlet structures for stilling high velocity flows from conduits have taken a variety of forms depending on physical and economic factors of the site and structure. Performance characteristics, general site

a d a p t a b . i l i t y and economic c o n s i d e r a t i o n t o f a c i l i t a t e judgment i n d e c i s i o n between a l t e r n a t e c h o i c e s i s p r e s e n t e d . The s e v e r a l d e s i g n c h a r t s e l i m i n a t e many s t e p s and h o u r s o f work f o r q u a n t i t y and c o s t estimating. P e r h a p s t h e most time s a v i n g o p e r a t i o n i n t h i s manual i s t h e summary s h e e t and p r o c e d u r e f o r p r e p a r i n g c o n s t r u c t i o n drawings. T h i s concludi n g s t e p opens t h e door t o t h e s e v e r a l a l t e r n a t i v e s and c o n s i d e r a t i o n s i n composing a set of c o n s t r u c t i o n d r a w i n g s f o r g a t e d o u t l e t a p p u r t e n a n c e s f o r e a r t h dams. C l a r i t y of c o n s t r u c t i o n p l a n s t h a t p r e s e n t t h e d e s i g n d e c i s i o n s made i n p r e c e d i n g s e c t i o n s of t h e manual i s i m p o r t a n t . N e a t n e s s , l e g i b i l i t y and c l a r i t y i n p l a n s c r e a t e a p s y c h o l o g i c a l r e s p o n s e i n t h e b u i l d e r c o n d u c i v e t o b e t t e r q u a l i t y work t h a n t h e r e s p o n s e t o p o o r l y d r a f t e d and v a g u e l y p r e s e n t e d d e t a i l s . The i d e a s o f f e r e d p e r m i t maximum c l a r i t y and minimum e f f o r t t o make a p r o f e s s i o n a l p r e s e n t a t i o n of p l a n s , c o n s i s t e n t w i t h t h e q u a l i t y o f d e s i g n and h e l p f u l t o b o t h b u i l d e r and c o n s t r u c t i o n e n g i n e e r i n g e t t i n g a good j o b done. It i s beyond t h e s c o p e of t h i s manual t o e v a l u a t e s t o r a g e r e q u i r e m e n t s and downstream w a t e r n e e d s . I n t h i s respect each i n s t a l l a t i o n i s u n i q u e and c a n n o t b e s t a n d a r d i z e d . Embankment a n a l y s i s h a s a l s o b e e n omitted a s a subject requiring individual a t t e n t i o n .

The c o n c e p t of t h e STANDARD DAM f o r p u r p o s e s o f h y d r a u l i c d e s i g n i s a b a s i c embankment s h a p e and a f u l l r e s e r v o i r d i s c h a r g i n g a t t h e t o e o f t h e dam t h r o u g h a c o n d u i t . A s u s e d i n t h i s manual, t h e c r o s s s e c t i o n o f t h e s t a n d a r d dam c o n s i s t s o f a n u p s t r e a m s l o p e o f 3:1, a t o p w i d t h o f 2 fi 5 f e e t , and a downstream s l o p e o f 2 :1. The s t a n d a r d i z e d i n l e t , s t e m p e d e s t a l and l i f t p e d e s t a l a r e d e t a i l e d f o r t h e 3 : l s l o p e . H y d r a u l i c l o s s e s a r e b a s e d on a c o n d u i t l e n g t h a s s o c i a t e d w i t h t h e d e s c r i b e d embankment p r o f i l e , f u l l r e s e r v o i r , and a f r e e o u t f a l l . Some of t h e d e s i g n c h a r t s and d e t a i l s a r e b a s e d on t h i s c o n f i g u r a t i o n and a r e n o t a p p l i c a b l e where t h e s e c o n d i t i o n s are n o t met. S p e c i f i c c h a r t s where t h e s e c o n d i t i o n s a p p l y a r e : F i g u r e s B - 1 , 2 , 3 , 4 ; C-4, 5 ; F-1, 2 , 3, 4 , 11. I f t h e c o n d u i t i s e x t e n d e d beyond t h e t o e of t h e dam, t h e o u t l e t i s submerged o r t h e r e s e r v o i r o n l y p a r t i a l l y f u l l , t h e hyd r a u l i c s y s t e m , u s i n g t h e s e f i g u r e s , s h o u l d b e s i z e d u s i n g a n EQUIVALENT DAM h e i g h t . See F i g u r e A-1. The e q u i v a l e n t dam h a s a f i c t i t i o u s h e i g h t t h a t makes i t e q u i v a l e n t t o t h e s t a n d a r d dam w i t h r e s p e c t t o h y d r a u l i c operation.

*

+

Art o v e r a l l p e r s p e c t i v e of t h e manual c o n t e n t and u s e i s p r e s e n t e d i n

F i g u r e A-2, P r o c e d u r e Flow C h a r t . T h i s c h a r t f o l l o w s t h e normal s e q u e n c e i n s e l e c t i o n and development of t h e d e t a i l s of g a t e d o u t l e t a p p u r t e n a n c e s . I t shows t h e m a j o r d e c i s i o n s t h a t might a f f e c t a l t e r n a t e s e l e c t i o n r e q u i r e d a t v a r i o u s p o i n t s i n t h e development.

*

The d i f f e r e n c e between t h i s t o p w i d t h compared w i t h one b a s e d on w i l l have l i t t l e e f f e c t on t h e p r e l i m i n a r y h y d r a u l i c p r o p o r t i o n i n g of t h e c o n d u i t .

H

+ 5

35

uf/et Structure I

STANDARD DAM

Out/e t Structure

e--1 L-

-A

Extended Conduit

EQUIVALENT DAM

Portio//y F u / / Reservoir fCrifico/ Conditionl

merged Outjet

-----

I

EQUIVALENT DAM

FIGURE A - l

S T A N D A R D - EQUIVALENT DAM E W P U n i t Portland Oregon

7

I

I\

YES

FIG. E - 7

/

ADJUST SYSTEM H E A D . S A F BASIN N E H 14

PWD BASIN

-

---b

7

FIG. F-1

POOL ?

CONSIDER IMPACT BASlN

,

CANTILEVER ADEOUAT

NO ARMOR FIG. F- 4

IMPACT BASIN

i + 7 L CONSIDERATI

CANTILEVER WITH ARMOR

ARMOR

SUMMARY SHEETS COMPLETED

'

=

' DRAFTING

STOP

SECTION B

.HYDRAULICS

Contents I

.

. .

I1

I11

. V.

IV

VI

.

VII.

VIII

.

..................... LOCATIONOFCONTROL . . . . . . . . . . . . . . . . . . FULL PIPE FLOW . . . . . . . . . . . . . . . . . . . . PARTIAL PIPE FLOW . . . . . . . . . . . . . . . . . . . CAVITATION . . . . . . . . . . . . . . . . . . . . . . USE OF CHARTS AND GRAPHS . . . . . . . . . . . . . . . A . F u l l P i p e Flow With Gate F u l l y Open . . . . . . . . 1. F i g u r e s B-1 t h r o u g h B-4 . . . . . . . . . . . . 2 . F i g u r e s B-5 t h r o u g h B-10 ............ B . P a r t i a l Gate Opening . . . . . . . . . . . . . . . ........ 1. P a r t i a l P i p e Flow. F i g u r e B-11 2 . F u l l P i p e Flow. F i g u r e s B-12 t h r o u g h B-17 . . . REVIEW . . . . . . . . . . . . . . . . . . . . . . . . EXAMPLE PROBLEM . . . . . . . . . . . . . . . . . . . . INTRODUCTION

Page B-1 B-2 B-2 B-3 B-3 B-3 B-4

B-4 B-4

B-5

B-5 B-5

B-7

B-7

-

SECTION B

HYDRAULICS

Figures Page B-1

Full Pipe Flow

-

Stage Discharge, n

=

0.011

B-2

II

II

II

11

II

n = 0.012

B-3

I1

I1

II

It

I1

n = 0,013

B-4

II

II

II

11

If

B-5

11

11

II

B-6

-

n = 0.024

B- 7

11

II

I1

11

11

B-8

II

tl

II

II

H

B- 9

11

11

I!

II

If

B-10

11

11

I1

It

II

... ...

B-13 B-14 B-15 B-16

n = 0.011

. ...

n = 0.012

...

B-19

n = 0.012

...

B-20

n = 0.013

,

..

B-21

n = 0.024

...

B-22

..

B-23

Entrance Loss Coefficient

Discharge for Full Pipe Flow

... ...

B-17 B-18

B-11

Free Discharge Through Partially Open Gates

B-12

Gate Headloss Coefficient ( K ~ ) Full Pipe Flow

B-13

Head Loss Coefficients for Circular and Square , Conduits Flowing Full

B-26

Discharge of Circular Pipe Flowing Full, n = 0.011

B-27

n = 0.013

B-28

B-14 B-15

.....

11

11

11

11

11

"

,

..

.. .

B-25

SECTION B I.

-

HYDRAULICS

INTRODUCTION Selecting the proper gate and outlet conduit size, in many cases, will be based on a head that is less than that with a full reservoir. This results when the water needs are less at the beginning of a season at the time the reservoir is full. As the reservoir level drops, the water requirements can increase. Obviously the gate and conduit system should be designed for this critical discharge-head relation. For less critical conditions, the system would be operated with the gate partially closed. Less obvious, however, is the possibility that the system may be operated with full head at full gate opening exceeding design discharge. This condition will be the critical one for certain outlet structures and can materially add to the cost of the system. Whether or not the outlet is sized for design discharge or maximum discharge requires judgment with the greater capacity recommended. The minimum diameter of the outlet conduit may be set by Service and individual state requirements and varies from no restriction to 30 inches. An outlet conduit diameter of not less than 6 inches, preferably 10 inches, is recommended. Minimum diameter may also be established by the length of time it takes to dewater a reservoir by gravity flow. Recommended flow duration at full gate opening should not exceed 10 days. Factors that determine the flow in a gated outlet include variables as the size, shape and type of control gate and conduit used, the slope, length and roughness of the conduit, the inlet and outlet conditions and the head on the system. The combined effect of any of these factors may determine the flow in the system. The nomographs and charts in this section were prepared to provide the engineer with the hydraulic relationships commonly encountered in the design of small gated outlets. The discussion of "~ocationof Control", "Full Pipe Flow" and "Partial Pipe Flow" is a simplification of actual conditions, in some cases to a point that can be misleading to the unwary. Many problems are associated with the calculation of water surface profiles in a circular cross-section on a fixed grade line. The major ones are: (1)

The effect of air entrainment and consequent bulking of the flow,

Determination of energy loss'for the bulked flow and its variable "n" value, Effect of pipe joints, elbows, gates, etc. Geometry of the inlet for both partial and fully open conditions as well as accuracy in evaluating the tailwater elevation, The certainty that the conduit, on a compressible foundation, is subject to joint rotation and elongation that make the grade line of the conduit indeterminate. The rest of the hydraulics section should be read keeping in mind that inlet control means partial pipe flow and outlet control means full pipe flow. LOCATION OF CONTROL Location of the control from the hydraulic standpoint dictates whether the conduit flows full or partly full and thereby establishes the head-discharge relationship. Slope of the pipe and the tailwater level are factors that determine location bf the control. The slope may be mild or steep, that is, it may be flatter or steeper than the slope at which a given discharge will just support flow at a critical stage. For either a mild or steep slope, the control may shift from inlet to outlet depending on the head, tailwater, and gate opening. For partial pipe flow, the control is normally at the inlet where orifice conditions control the discharge. For full pipe flow the control is at the outlet, and the total head on the system is determined by the elevation of the tailwater. In the case of free outfall at the outlet, the tailwater elevation is considered the center of the pipe outlet. 111.

FULL PIPE FLOW Full pipe flow usually occurs in long conduits with a mild or flat slope or where the outlet is submerged. The depth of water at the entrance must be greater than 1.2 times the inside diameter of the pipe to produce full pipe flow. Partial pipe flow may occur with the inlet submerged if the slope is steep or if the pipe is short enough so that a hydraulic jump does not occur in the length of the pipe and air is admitted through the outlet or by means of a vent. Full pipe flow conditions control for nearly all gate openings if the conduit is on a mild slope.

IV.

PARTIAL PIPE FLOW Partial pipe flow usually occurs in short conduits with sharp comers or inward projecting entrance and low heads. Partial pipe flow may also occur where the conduit is on a steep slope with partial gate openings and free outfall. In this case the inlet acts as an orifice to control the flow. The inlet must be vented re have orifice control. The vent may be a vent-pipe or the airspace maintained above the water surface during partial pipe flow with free outfall and air admitted from the outlet. If the conduit flows full at any point and the inlet is not vented, the high velocity flow will carry away entrapped air. The pressure in the pipe can then drop below atmospheric pressure and cause operation problems and structural damage.

V.

CAVITATION Localized constrictions, surface irregularities, and abrupt changes in alignment provide conditions for potential structural damage. This damage is caused by the successive formation and collapse of vapor pockets in low pressure areas associated with high velocity flow. The collaps~of vapor pockets cause implosions that result in pitting of the concrete or the metal conduit surface. The pitting then accelerates the effect of cavitation by intensifying the negative pressures. Several measures will reduce the potential for cavitation: streamlining of entrances and slots; increasing the crosssectional area; or, introducing air by venting to the low pressure area. Venting the conduit just downstream of the gate is recommended. Further discussion of vent pipes is presented in Section C, Inlets. Conduits carrying flow with velocities in excess of 25 fps should be studied for cavitation potential.

VI.

USE OF CHARTS AND GRAPHS

It should be recognized that these charts and graphs were developed for average conditions. Some of the relationships were derived from model studies. The curves or values may be an average of the results of these studies. Any deviation from the condition of the study could change the results; however, these relationships will give usable answers for most design

problems in small gated outlets. If exact values are required for a specific structure, detailed computations will be necessary to evaluate the exact conditions and requirements for that structure.

A.

Full Pipe Flow With Gate Fully Open 1.

Figures B-1 through B-4 Figures B-1 through B-4 were developed to quickly determine the pipe size and flow velocity for a given'height of dam and discharge. THESE CHARTS APPLY TO FULL RESERVOIR CONDITIONS. For lower stages, chart discharges will be high and Figures B-6 through B-10 should be used. Each chart gives the relationships for a different conduit roughness (Manning's "n" value). They apply for an entrance condition of a fully open gate with square corners and a single miter bend. Energy loss is based on a pipe length for an embankment slope of 3:l upstream and 2 : l downstream. The top width of the embankment is 2 m+5where H is the vertical distance from the spillway crest to gate centerline. A combined headloss coefficient of 1.24 was used for the entrance and elbow. The losses for these conditions are considered to be average for small dams with the head range shown on the charts. The charts are entered with known values of head and discharge. The pipe diameter and velocity of flow are determined from the curves. If the point falls between two diameter lines, the larger diameter must be used to obtain the given discharge and velocity can be determined directly. The most common pipe sizes for concrete and corrugated metal pipe were used in the construction of these charts. Relationships for other pipe sizes may be determined by interpolation.

2.

Figures B-5 through B-10 Figures B-5 through B-10 give the relationships for full pipe flow with various entrance conditions and variable pipe lengths. THEY ARE FOR USE IN HYDRAULIC ANALYSIS WHERE THE RESERVOIR IS LESS THAN FULL OR WHERE THE PIPELINE EXTENDS BEYOND THE TOE OF THE DAM. They are also valid for the full reservoir stage although additional computation is required to find flow velocity. Figure B-5 is used to determine the loss coefficient (Ke) for various entrance types. Figures B-6 through B-10

present the relationships of head, length of pipe, and discharge for various entrance loss coefficients in nomograph form. These nomographs have been developed for four pipe roughness factors (Manning's "n" values) that apply to most installations. The difference between Figures B-7 and B-8 is the head range. Example solutions are shown on the nomographs. Note that the entrance headloss coefficients (Ke) on Figure B-5 represent the loss for the entrance type, including any bends or corners connected with the inlet, as shown by each illustration. Headloss coefficients for partial gate openings are not included on this chart but may be obtained from Figure 3-12. B.

Partial Gate Opening 1. Partial Pipe Flow, Figure B-11

Figure B-11 was developed to determine the flow characteristics at partial gate openings with partial pipe flow. This nomograph gives the relationships for orifice control at the inlet. However, partial pipe flow should be compared with the full pipe flow condition to determine which controls the discharge. To determine if full or partial pipe flow controls, enter Figure B-11 with the given head, gate opening and gate size. The resulting discharge is then noted. For partial pipe flow to exist, this discharge must be less than the normal full pipe flow discharge that would occur with the particular pipe size and slope with free discharge. Calculations for this condition are described in Section 2 below.

2.

Full Pipe Flow, Fipures B-12 through B-17 The normal discharge for full pipe flow for a given pipe diameter and slope can be determined ,from Figures B-14 through B-17 (ES-54). If the full pipe flow determined from the above figures is less than the discharge as determined from Figure B-11, the conduit is flowing full and calculations must be made to determine the correct discharge. The hydraulics of full pipe flow are based on these fundamental relationships:

From these the following equations are derived:

where

Q D H

discharge in cfs inside diameter of conduit in feet = total head in feet (upstream water surface to tailwater surface or center of pipe at outlet for free outfall) A = flow area, square feet V = flow velocity, feet per second IK = summation of headloss coefficients including K,, entrance loss, Kg, gate loss, Kb, bend loss, K Q, pipe friction P loss, KO, exit loss, and any other losses involved. Headloss coefficients are related to the velocity in the conduit at full pipe flow. Note that the addition of a headloss coefficient for partial gate openings (K ) will modify the headloss coefficient g for the entrance (Ke) as shown in Figure B-5. Subtracting 0.5 from the value of Ke for the fully open gate results in a bend loss ( K b ) . Values for Kg and Kb replace the combined loss Ke used for the fully open gate. = =

The headloss coefficient (Kg) at various gate openings can be determined from Figure B-12. Gate loss coefficients for both circular leaf and square bottom gates with gate openings from 10 to 100 percent are included on this figure. The circular leaf is found on light duty gates while most heavy duty gates have straight bottom. Entrance headloss coefficients (Ke) can be determined from Figure B-5. ~rictionheadloss coefficients (Kp) for various pipe sizes to be combined with the pipe length can be determined from Figure B-13.

i

The conduit exit headloss is considered to be equal to the headloss at a sudden infinite enlargement. The exit headloss coefficient is, therefore, considered to equal 1.0. For special conditions such as bends (other than those illustrated), enlargements or contraction, and refinement in hydraulic analysis refer to NEH, Section 5, Hydraulics.

VII.

REVIEW Before going into the selection and detailing of appurtenances, the overall hydraulic picture of the outlet system should be reviewed. Recognizing that some water level other than full reservoir may be the controlling head for selecting conduit size, has the critical water level been determined? The system capacity is affected by the individual head losses: (1)

configuration of the inlet whether re-entrant or flush, (2) bend, whether single or multiple miter, (3) effect of the vent pipe on the system head, ( 4 ) type of pipe-corrugated metal, monolithic concrete, or cylinder pipe, etc., as it effects the hydraulic roughness coefficient, (5) pipe diameter, whether it is a stock size and available locally, (6) the outlet, whether submerged or discharging freely at atmospheric pressure, etc,

VIIT. EXAMPLE PROBLEM The following example deals with the hydraulic design of an outlet for a small earthfill dam. It is assumed that the height, slopes and top width of the dam are known and the elevation of the conduit inlet and outlet are given. It is also assumed that the discharge requirements for the outlet have been determined from hydrologic data and downstream flow requirements. Given : An earthfill dam with the height and slopes, as shown in the following sketch will require an outlet conduit to satisfy the following : 1. 2. 3.

Discharge 40 cfs at maximum reservoir level Discharge 20 cfs at intermediate levels. Discharge 15 cfs as base flow with water level at El 110.0.

A square bottom slide gate is to be used.

Top o f dam El /25.0

Homogeneous Embanhment

S=

i

o.o/o

Center of gote El /02.2

Determine: Select the conduit size and associated gate openings to satisfy the listed conditions. Problem Analysis: 1.

Determine Manning's roughness coefficient "n" for several types of conduits available, or to be considered.

2.

Find conduit diameter required to carry required discharges for (a) full reservoir, and (b) partly empty reservoir.

3.

Compare answer in 2 (a) and (b) above, determine critical condition and select conduit size.

4. Find gate opening required to limit discharge for noncritical head-conduit diameter relation.

5.

Check availability of gate and conduit selected.

1.

Determine the diameters of several types of pipe to meet the discharge requirements (check local availability).

Y

a.

For maximum head maximum d i s c h a r g e , u s e F i g u r e s B-1 (These f i g u r e s a p p l y f o r t h e f u l l resert h r u B-4. v o i r condition.) E n t e r each c h a r t w i t h Q Find:

b.

=

40 c f s and H

=

20 f t .

Steel pipe (n = 0.011) = 19.5", u s e 20" d i a . Concrete p i p e (n = 0.013) = 20.5", u s e 21" d i a . CM, p i p e (n = 0.024) = 24" d i a .

Find t h e d i a m e t e r of p i p e f o r 20 c f s a t t h e minimum head. F i g u r e s B-5 t h r u B-10 should be used because t h e system head i s l e s s t h a n t h a t f o r f u l l r e s e r v o i r . These f i g u r e s a r e e n t e r e d w i t h t h e followihg g i v e n data: Entrance l o s s Ke = 1.24 from F i g u r e B-5 o r s e e d i a gram on a p p r o p r i a t e F i g u r e s B-6 t h r u B-10. Conduit l e n g t h

=

131 f t from problem s k e t c h

Discharge Q = 20 c f s Head H = 9 f t ( E l 110.0 Find:

2.

-

100.9)

) Operation ) Requirements

Steel pipe (n = 0.011) = 1 7 . 7 , u s e 18" d i a . Concrete p i p e (n = 0.013) = 18" d i a . (n = 0.024) = 21" d i a . CM p i p e

From a comparison of t h e c o n d u i t d i a m e t e r s r e q u i r e d f o r t h e two d i s c h a r g e c o n d i t i o n s , i t i s obvious t h e c r i t i c a l d i s c h a r g e i s f o r maximum head c o n d i t i o n . To s a t i s f y t h e s i t e r e q u i r e m e n t s , any one of t h e f o l l o w i n g w i l l s a t i s f y t h e discharge needs: Steel pipe Concrete p i p e CM p i p e

20" d i a m e t e r 21" II II 24"

S i n c e t h e rest of t h e procedure i s s i m i l a r f o r a l l t h r e e p i p e t y p e s , o n l y t h e 21" d i a m e t e r c o n c r e t e p i p e w i l l b e used t o c o n t i n u e t h e example t o completion.

3.

Determine t h e g a t e opening t o p r o v i d e a d i s c h a r g e of 20 c f s w i t h t h e r e s e r v o i r a t E l 110.0. For f r e e o u t f a l l , t h e w a t e r c o n d u i t i s c o n s i d e r e d t o be The t a i l w a t e r e l e v a t i o n f o r c o n s i d e r e d t o be 100.9 f t .

s u r f a c e a t t h e o u t l e t of t h e a t t h e c e n t e r of t h e p i p e . t h i s example i s , t h e r e f o r e , The head on t h e system w i t h

t h e r e s e r v o i r a t t h e permanent p o o l e l e v a t i o n i s 110.00 - 100.9' = 9 . 1 ft. The head on t h e c o n d u i t i n l e t i s 110.00 - 102.2 = 7 . 8 f t . Check f o r f u l l p i p e f l o w t o s e e i f t h i s c o n d i t i o n c o n t r o l s t h e d i s c h a r g e i n t h e system. E n t e r F i g u r e B-15 f o r n = 0.013 w i t h D = 21" and S = 0.010. Find Q = 1 6 c f s . T h e r e f o r e , t h e p i p e w i l l f l o w f u l l a t 20 c f s ( o p e r a t i o n r e q u i r e m e n t s ) and F i g u r e B-12 a p p l i e s . T o r e d u c e t h e d i s c h a r g e , t h e g a t e w i l l have t o b e p a r t i a l l y c l o s e d . Approximate g a t e c l o s u r e can b e d e t e r m i n e d from t h e r e a r r a n g e d d i s c h a r g e e q u a t i o n from page B-6.

S u b s t i t u t i n g known v a l u e s of D , H and Q

A l s o , knowing t h e f o l l o w i n g h e a d l o s s c o e f f i c i e n t s , P i p e f r i c t i o n ( n = 0.013, d = 21", from F i g . B-13 = (0.0148) 1 3 1 Bend, s i n g l e m i t e r ( 3 : l s l o p e ) from F i g . B-5 Kb = 1 . 2 4 - 0 . 5 KO Outlet, Gate, Kg

Kp = 0.0148)

~~a

Then t h e t K and Kg = T K

=

-

K (Kpj'+

a + Kb Kb

+ KO + K + KO) = 8.2

=

1.94

= = =

0.74 1.00

=

- 3.68

Kg 3.68

+ Kg

= 4.82

E n t e r F i g u r e B-12 w i t h t h i s v a l u e of Kg and assume a s q u a r e bottom g a t e l e a f , f i n d a p p r o x i m a t e g a t e opening o f 48% f o r t h e 20 c f s a t a head of 9 . 1 f t . 4.

Determine t h e g a t e o p e n i n g t o p r o v i d e 1 5 c f s d i s c h a r g e w i t h t h e r e s e r v o i r l e v e l a t E l 1 2 1 . 0 and a l s o a t E l 110.0. The head on t h e c o n d u i t i n l e t w i t h t h e r e s e r v o i r l e v e l a t t h e maximum e l e v a t i o n i s 1 2 1 . 0 - 102.2 = 18.8 E t .

With t h e r e s e r v o i r a t E l 110.0, t h e head on t h e c o n d u i t 102.2 = 7.8 f t . i n l e t i s 110.0

-

From t h e p r e v i o u s check f o r f u l l p i p e flow, i t was determined t h a t t h e normal f u l l p i p e flow a t t h e g i v e n s l o p e was 16 c f s . The p i p e would, t h e r e f o r e , flow p a r t l y f u l l f o r a d i s c h a r g e of 1 5 c f s provided t h a t t h e o u t l e t was n o t submerged. F i g u r e B - 1 1 i s t h e n used t o determine t h e g a t e opening. E n t e r t h e nomography w i t h H = 18.8 f t and e x t e n d a l i n e through Q = 15 c f s t o t h e p i v o t l i n e . The d i a m e t e r of 1 . 7 5 i s connected t o t h e p o i n t on t h e p i v o t l i n e and For a s q u a r e bottom s l i d e extended t o f i n d Cv = 0.175. g a t e t h e opening c o r r e s p o n d i n g t o Cv = 0.175 i s approxi m a t e l y 32 p e r c e n t of t h e d i a m e t e r . T h i s s e t t i n g would p r o v i d e t h e r e q u i r e d b a s e flow d i s c h a r g e of 1 5 c f s when t h e r e s e r v o i r l e v e l was a t t h e maximum e l e v a t i o n . For H = 7.8 ft, Q = 1 5 c f s , and D = 1 . 7 5 f t , Cv was determined t o b e 0.27. For a s q u a r e bottom g a t e , t h e g a t e opening was determined t o be a p p r o x i m a t e l y - 4 3 percent. This s e t t i n g w i l l allow t h e required base flow ( d i s c h a r g e ) of 15 c f s when t h e r e s e r v o i r l e v e l i s a t E l 110.0. The 2 1 i n . d i a m e t e r p i p e s a t i s f i e s t h e f u n c t i o n a l r e q u i r e ments. A q u i c k check of a g a t e c a t a l o g u e shows a 2 1 i n . g a t e a v a i l a b l e a s a s t o c k i t e m f o r t h e system head. I n t h e e v e n t a c o n d u i t i s s e l e c t e d f o r which a s t o c k s i z e gate is not available, the next l a r g e r gate w i l l be used. A s h o r t t r a n s i t i o n c a s t - i n - p l a c e i n t h e i n l e t s t r u c t u r e i s recommended f o r t h i s s i t u a t i o n .

006 00 1 001 009 00s 00 b

OOE

00 2

001 06 08 0L

09 0s

o*

OE

01 6

8 L 9

E f

E

Z

FIGURE 8 - 2

FULL PIPE FLOW STAGE DISCHARGE E W P Unit Portland, Oregon

0001 006 008

OOL

FIGURE B- 3

FULL PIPE FLOW STAGE DISCHARGE E W P Unit Portland, Oregon

OOE

FIGURE 8 - 4

FULL PIPE FLOW STAGE DISCHARGE EWP Unit Portland, Oregon

-

Straight l n l e t Square Cornered

Flow

Flow

Straight lnlet - Inward Projecting -Square Cornered

Double M i t e r Bend S q u a r e Corner

K, = 0.50

Ke

= 0.78

Flow

___C)1

-

Single M i t e r Bend S q u a r e Corner

SLOPE

9(

P

Flow

k* Single

1 Double

* - Includes

Kg

Ave.

1.24

0.99

Bend L o s s C o e f f i c i e n t 0.5 of t h e listed value is f o r the inlet, the remainder for the bend.

Trash rack losses are negligible f o r the standard inlet.

B-5 FULL PIPE FLOW ENTRANCE LOSS COEFFICIENT FIGURE

EWP Unit Portland, Oregon

H T = Head in feet

= 0 = n = L = Q = Ke

30

Entrance loss coefficient Diameter of pipe in f e e t ~ a n n i n ~ lroughness s coefficient Length of culvert in f e e t Design discharge rote in cfs

40

50

FIGURE B-6 REFERENCE After Bureau of Public Roads Charts

DISCHARGE FOR FULL PIPE FLOW n=0.011 EWP U n ~ tPortland, Oregon

EQUATION

:

HT

=

2. 5 2 0 4 ( I + Ke) +

466.18 n2 L D 16/3

H r = H e a d In f e e t E n t r a n c e loss c o e f f i c i e n t D = D i a m e t e r of pipe In f e e t n = ~ o n n i n roughness ~ ' ~ coefficient = L e n g t h o f c u l v e r t In f e e t Q = Design discharge rate in c f s

Ke =

t

FIGURE 8 - 7 REFERENCE Af ter Bureau of Public Roods Charts

DISCHARGE FOR FULL PIPE F L O W n=0.012 EWP U n i t P o r t l a n d , O r e g o n

HT : Ke = 0 = n = L = Q =

Head In feet Entrance loss coeffrc~ent D ~ o m e l e ro f plpe in feel ~ a n n l n g ' sroughness coeffoc~enl Length o f culvert In f e e t D ~ s c h a r g er o t e In c f s

FIGURE 8 - 8 REFERENCE After Bureau of Public Roads Charts.

DISCHARGE FOR FULL PIPE FLOW n=0.012 EWP Unit P o r t l a n d , Oregon

H T = H e a d in f e e t Ke Entronce loss coefficient D = Diameter o f pipe in feet n = ~ a n n i n g ' s roughness coefficient L = Length o f culvert in feet Q = Design discharge rate in cfs

FIGURE 8-9 REFERENCE After Bureau o f Public Roods Charts

DISCHARGE FOR FULL PIPE FLOW n=0.013 EWP Unit Portland, Oregon

M-ZZ

SUBMERGED O U T L E T

HT = Head in feet Ke = Entrance loss c o e f f i c i e n t D = Diameter of pipe in f e e t n = ~ a n n i n g ' sroughness coefficient L = Length o f c u l v e r t in f e e t Q = Discharge r a t e in c f s

FIGURE B - I 0 REFERENCE After Bureau of Public Roads Charts

DISCHARGE FOR FULL PIPE F L O W n=0.024 E W P U n i t Portland, Oregon

Light Duty Gate

Heavy Duty Gate -\

Partial F l o w

d

0.6

,c.0.5

L

$! $ Q,

0-4

2 0.3

Circ u lor leof

g 0.2

Square bottom leaf

&

C

.$ 0.1

Q 0

0

10

20 30 40 50 60 70 Gote opening in percent D

80

90

For fully open gotes, fill pipe ,flow, and embankment slopes o f 3.'/ ond 2.'1 refer to Figures B-/, B-2, B - 3 , 8 - 4 For fu/& open gotes and f u N plpe f/ow with o voriefy o f entrances refer to Figures 8-5, 8-6, B - 7, B - 8 , B - 9 , 8 - 1 0

'

It 0.05

Example .' ~ = 1 8 . 8 ' , Q=l5 cfs, D= I. 75' Read Cv = 0.175 Gate opening for square bottom leaf = 3/%

t

U =6.32C ~ D ' H ~ Q = Design discharge rate in cfs Cv= Gate discharge coef ficien f D = Diameter of pipe in feet H = Head in feet measured to center line o f conduit

REFERENCE: Ball, J. W.,"~imitotionsof ~ e t e r ~ a t e s ,ASCE " Journal of lrrigat~onond Drainage, Dec. 1962, p. 26, paper No. 3359.

FIGURE B - l l

FREE DISCHARGE T H R U PARTIALLY OPEN GATES EWP Unit Portland, Oregon

100

FIGURE 8-12 REFERENCE: W.E.S. Hyd.Chort 330-1

GATE HEADLOSS COEFFICIENT (Kg) FULL PIPE F L O W E W P Unit Portland, Oregon

h'6dD LOSS ci%fff/C/dNTKc, FOP SQUARE COPVDU/T/?L OW/A/G FVl L

29. /6nz

XC =- f

s/ze

f/oW area

MAA/A'/AfG'S COZFF/C/&~T Of ROUGHNESS "n

fee/

sqff

00/2160/310.0/4]60/5~00/6 o = Cross - sect/bno/ urau o f f / u w I n sq.f f D = /!side d/umdef o f jq'k /h /hches. q = Acce/erqt/bn o f qrow/fy = 32.2 f f per sec.

lad1/,f

4 = Loss o f

heud

/i,

feef due fo fric.'/on in /enyth L.

Kc = h'e.od/uss coeff/oen/ for squure condulf f/owing fu/L Kp = L = n = 4= r = v =

Heud/oss coefficienf fcr cictu/ur pipe f/awing fu//. Lengfh of conduif I n feel: Munningk coefficient of roughness. Discharge o r copucify I n CIA ft p e r sec. h'ydrou//'c radius /h feet. Mean ve/ocity i n f t per sec.

Me heod /as in 300ft o f 24 in dhn. concrete pipe f/owinq f u / / and d/schurginy 30 c f s . Assume n = QO/5 Q 30 v2 v z -0 - --3.14 - 9 5 5 f p s ; =

E,xomp/ef : Compufe

-

E1:/.4.?fi

Exump/e 2: Cbmpufe f/lr d/&zhurge o f 0 Z S O f t , 3 x 3 squure conduit f/ow/nq fu// i f the /OSS o f heud ;J defermined t o be 2.25 fi! Assume n =O.U/4

FIGURE 6 - 13 REFERENCE: ES - 42

HEAD LOSS COEFFICIENTS FOR CIRCULAR AND SQUARE CONDUITS FLOWING FULL EWP Unit Portlond, Oregon

REFERENCE:

ES- 54

FIGURE 6-14

DISCHARGE OF C I R C U L A R PIPE FLOWING FULL F W P l l n i t Pnrtlnnd

Orennn

REFERENCE:

ES- 5 4

FIGURE 8-15

DISCHARGE OF CIRCULAR PIPE FLOWING FULL EWP Unit Portland, Oregon

REFERENCE:

ES-54

FIGURE 8-16

DISCHARGE O F CIRCULAR PIPE FLOWING FULL EWP Unlt Portland, Oregon

REFERENCE:

ES- 54

FIGURE 0-17

DISCHARGE OF CIRCULAR PIPE FLOWING FULL E W P U n ~ tPortlond, Oregon

SECTION C .INLET STRUCTURE Contents I

.

. I11. I1

IV

.

V.

. V I I. VI

...................... GENERAL CRITERIA . . . . . . . . . . . . . . . . . . . . NOMENCLATURE AND GENERAL NOTES . . . . . . . . . . . . . STANDARD INLET . . . . . . . . . . . . . . . . . . . . . A . Structure Size . . . . . . . . . . . . . . . . . . . B . TrashRack . . . . . . . . . . . . . . . . . . . . . C . Inlet Protection . . . . . . . . . . . . . . . . . . VENT PIPE . . . . . . . . . . . . . . . . . . . . . . . . QUANTITY SURVEY . . . . . . . . . . . . . . . . . . . . . EXAMPLE ........................ INTRODUCTION

Page C-1 C-1 C-1

C-2 C-2 C-3 C-3

C-3 C-4 C-4

Figures C-1 C-2 C-3 C-4 C-5

........... Inlet Structure . . . . . . . . . . . . . . . . . . . . . Alternate Trash Rack . . . . . . . . . . . . . . . . . . Inlet Protection . . . . . . . . . . . . . . . . . . . . V e n t Pipe Diameter . . . . . . . . . . . . . . . . . . .

Nomenclature .Water Control Gates

C-7 C-9 C-11 C-13 C-14

SECTION C I.

-

INLET STRUCTURE

INTRODUCTION Innumerable varieties of inlet structures are designed individually for essentially the same conditions and requirements. The standard structure in this section has evolved over'a period of years and incorporates details based on experience gained from a number of installations. This structure is for use with a 3:l upstream embankment slope. Two trash rack systems are given: one, more suitable for low head installation, and the other for higher heads where portions of the rack may need to be removed for maintenance without: the use of heavy duty lifting equipment.

A single miter elbow has been selected in preference to a multiple miter. Savings in head due to the improved hydraulics of the multiple miter elbow does not justify the additional cost of fabrication. 11.

GENERAL CRITERIA The standard inlet was designed using Class 3000 concrete with an allowable stress of 0.45 f ' , . If Class 4000 concrete is required, no change in detail is necessary other than to call for the higher strength concrete in the specifications. Intermediate grade steel was used with an allowable working stress fs = 20,000 psi. Reference is made to the following specifications (not included in the manual) as they affect the gate details: a. b.

111.

Construction Specification Nos. 71, 81. Materials Specification Nos. 553, 571, 572, 573, 581, 582.

NOMENCLATURE AND GENERAL NOTES Components of the rising and non-rising stem type gates are schematically illustrated in ~ i ~ u r eC-1. ' Non-rising stems have limited application to Service use. Their main use is for installations where straight stem alignment is not possible. A universal joint transmits torsional forces at a slope change that prohibits the use of a rising stem.

Of the four types of gate seat backs,-the one most used in the Service is the spigot back.

It is cast directly in the concrete

o r g r o u t e d i n t o p l a c e , and anchored b y p r e s e t b o l t s . It may a l s o b e connected d i r e c t l y t o s t e e l pipe. The s p i g o t back i s l i m i t e d i n a v a i l a b i l i t y t o t h e low and medium d u t y g a t e . Not a l l manuf a c t u r e r s supply t h i s type. The f l a n g e b a c k g a t e r e s i s t s w a r p i n g b e t t e r t h a n t h e s p i g o t b a c k . It i s u s e d t o a d v a n t a g e i n mounting on e x i s t i n g w a l l s . For l a r g e r , heavy d u t y g a t e s , t h i s t y p e i s used w i t h a t h i m b l e previously c a s t i n the receiving wall. The f l a n g e and s p i g o t back g a t e s e a t i s used p r i m a r i l y where t o p and b o t t o m wedges a r e r e q u i r e d and t h e g a t e c a s t d i r e c t l y i n a concrete structure. The f l a t back g a t e s e a t s h o u l d b e used w i t h a t h i m b l e . A t h i n c o a t o f f i b r a t e d m a s t i c s h o u l d b e p l a c e d between t h e c o n t a c t s u r f aces. The g a t e s e a t o p e n i n g may v a r y w i t h c l a s s o f g a t e . For l i g h t d u t y t h e g a t e s e a t o p e n i n g may b e c i r c u l a r . For h e a v i e r d u t y g a t e s t h e s e a t may h a v e a r e c t a n g u l a r o p e n i n g b u t t h e g a t e frame A r e c t a n g u l a r o p e n i n g i s used w i l l r e d u c e t o a c i r c u l a r opening. with s p e c i a l s e a t facings (usually bronze). Bronze seat f a c i n g s a r e recommended even w i t h l i g h t d u t y g a t e s . A t t h e time of f i n a l adjustment a l i g h t a p p l i c a t i o n o f waterproof g r e a s e s h o u l d b e a p p l i e d t o t h e s e a t f a c e s . Some l e a k a g e can b e e x p e c t e d : t h e maximum s h o u l d n o t e x c e e d 0 . 2 gpm p e r f o o t of p e r i p h e r y a t a f a c e p r e s s u r e e q u a l t o 1 6 f t of water.

IV.

STANDARD INLET A.

Structure Size Dimensions o f t h e s t a n d a r d i z e d i n l e t are t a b u l a t e d on The s i z e o f t h e i n l e t i s d i r e c t l y r e l a t e d t o F i g u r e C-2. t h e c o n d u i t d i a m e t e r and i s t h e same r e g a r d l e s s of t h e head Dimension ( 4 ) w i l l r e q u i r e a d j u s t m e n t when p i p e d i a m e t e r s o t h e r t h a n t h o s e l i s t e d i n t h e t a b u l a t i o n a r e used. This a d j u s t m e n t i s r e q u i r e d t o keep t h e r e s t of t h e d i m e n s i o n s c o n s t a n t f o r each s t r u c t u r e s i z e . S t r u c t u r e dimensions p e r t a i n t o an embankment s l o p e o f 3 : l . A typical standard drawing ( s i z e H - 21" c o n d u i t ) i s shown on F i g u r e H-3 of t h e completed example. I n l e t s t r u c t u r e s i z e J (36" c o n d u i t ) w i l l r e q u i r e change i f h y d r a u l i c c o n t r o l s a r e used w i t h t h e c y l i n d e r mounted a t t h e g a t e . D i s c u s s i o n of c o n t r o l s w i l l b e found i n S e c t i o n D.

B.

Trash Rack S t a n d a r d drawings f o r t r a s h r a c k s have n o t been developed because of t h e wide r a n g e i n s t r u c t u r e s i z e and head. Two a l t e r n a t e systems o f t r a s h r a c k s a r e p r e s e n t e d w i t h d e t a i l s and member s i z e s f o r each. Both a l t e r n a t e s p r o v i d e f o r a double c r o s s b a r t o r e d u c e l o n g i t u d i n a l member s i z e s f o r t h e h i g h e r heads.

C.

1.

F i g u r e C-2 one u n i t . lower head n o t exceed place.

c o n t a i n s d e t a i l s f o r t r a s h r a c k s welded i n t o T h i s c o n s t r u c t i o n i s recommended f o r t h e systems where t h e t o t a l r a c k weight would t h e a b i l i t y of two men t o s e t t h e r a c k i n

2.

F i g u r e C-3 p r o v i d e s d e t a i l s f o r t h e a l t e r n a t e r a c k system. For t h e l a r g e r c o n d u i t s i z e s o r h i g h e r h e a d s , t h e r a c k may be assembled one l o n g i t u d i n a l member a t a time. T h i s f i g u r e must be used w i t h F i g u r e C-2 f o r completing d e t a i l s .

I n l e t Protection Where t h e s o i l s u r r o u n d i n g t h e i n l e t s t r u c t u r e i s f i n e g r a i n e d w i t h low p l a s t i c i t y , p r o t e c t i o n should be provided on b o t h t h e s l o p e and t h e l e v e l approach a r e a . S i z e o f r o c k and e x t e n t of p r o t e c t i o n from c o n d u i t c e n t e r l i n e i s g i v e n T h i s f i g u r e was developed from t h e p r o c e d u r e i n F i g u r e C-4. p r e s e n t e d i n SCS T e c h n i c a l R e l e a s e No. 3.

VENT P I P E Vent p i p e s a r e recommended f o r a l l g a t e d o u t l e t s provided flow m e t e r s a r e n o t t o b e used i n t h e c o n d u i t . Vents were d i s c u s s e d p r e v i o u s l y i n S e c t i o n B , H y d r a u l i c s . The h y d r a u l i c a n a l y s i s a s a r e s u l t of v e n t i n g does n o t l e n d i t s e l f t o e x a c t a n a l y s i s . The net e f f e c t of a v e n t i s t o reduce d i s c h a r g e c a p a c i t y f o r t h e f r e e f l o w o u t l e t c o n d i t i o n ; t h e i n l e t c o n t r o l c a p a c i t y w i l l be minimum. The Recommended v e n t p i p e d i a m e t e r s a r e shown i n F i g u r e C-5. v e n t p i p e s i z e i s based on a maximum a i r v e l o c i t y of 100 f p s and n e c e s s a r i l y r e q u i r e s a n i n c r e a s e i n v e n t d i a m e t e r w i t h h y d r a u l i c head. A p o i n t of i n t e r e s t , maximum a i r demand o c c u r s w i t h a p a r t i a l g a t e opening. Three dashed l i n e s c u r v i n g upward t o t h e r i g h t r e p r e s e n t t h r e e f i x e d r a t i o s of v e n t s i z e s c a l l e d f o r by some m a n u f a c t u r e r s

under various conditions. ison only.

These lines have been added for compar-

A word of caution--if the installation involves an extended pipeline with outlet control, an oversized vent will result from use of Figure C-5 without modification.

If the outlet pipeline is extended beyond the toe of the embankment and outlet control exists, the vent pipe may be reduced from that given directly on Figure C-5. Explanation of this difference is based on.the fact that the'standard dam was used in developing many of the design aids. With an extended pipeline the additional friction losses reduce the carrying capacity of the system, thereby reducing the velocity and vent size requirement. The required vent size for the longer pipeline can be readily found by converting the proposed system to an equivalent standard dam (for calculation purposes only) and selecting the vent size accordingly. The following example should illustrate the principle involved.

A standard dam with a 20 inch conduit (n = 0.011) outletting at the toe of the embankment will carry 40 cfs at a 16 ft. head, see Figure B-1, and require a 1.5 inch vent pipe, see Figure C-5. If the pipeline was extended another 100 ft. (L = 170 ft.) beyond the embankment the discharge for the same head would be reduced to 35 cfs, see Figure B-6, because of the additional friction loss. The 20 inch conduit diameter with a lesser discharge is the same as a standard dam with a head of 11 feet, see Figure B-1. With this lesser equivalent head the vent pipe diameter can be reduced from 1.5 inches to 1.25 inches, from Figure C-5. QUANTITY SURVEY Concrete and reinforcing steel quantities are listed on Figure C-2. A refinement of these quantities based on conduit type and additional diameters is given in Table J-C1. EXAMPLE

Given:

Continuing the earth dam problem from Section B.

Determine: Type of gate back, size of trash rack members, diameter of vent pipe, extent of inlet protection and reinforced concrete quantities. Problem Analysis :

1. Find size of standard inlet to be used and its drawing number.

2.

Find size of trash rack members.

3.

Select other construction details and scale appropriate to reproduction method.

4.

Determine need for rock protection at i.nlet and size of rock and filter required.

5. Determine size of vent pipe required.

6. Find material quantities for the inlet. Solution: A spigot back gate is available in all three conduit sizes. This gate will be attached to the conduit, located on the proper slope and elevation, and inlet concrete placed. Referring to Figure C-2, it can be seen that the structure size for the 2 0 inch conduit should be a size G; a size H w i l l be used f o r the 2 1 inch and 24 inch conduits. Find the following items from the referenced figures. Standard Drawings (from Figure C-2) 20" conduit 21" and 24" conduits

7-N-20465G

7-N-20465H

Size of trash rack members - Using a single cross bar because of the low head on the inlet, the following may be found from C-2. Inlet

Longitudinal

G-1

1 112" pipe

H-1

2" pipe

Trash Rack Member Cross Bar A Cross Bar B

Z

4" x 318"

4" x 112"

4"

4" x 318"

4 1 9.5

4"

Construction details - Trash rack details are found on Figure C-2. Note that the lettering on these details is of a size and weight consistent with construction drawing requirements and a duplicate figure could be cut up and used in making a mosaic as explained in Section H, Drawing Layout and Summary. Inlet protection Figure C-5. Conduit size 2 0 W.S. 21 R/C 24 CMP

-

Recommended inlet protection is found on

Rock size d75

9" 9 112" 7 112"

Filter thickness

5" 5" 4"

R

4' 4' 4'

This protection should be provided if the soil adjacent to the inlet is fine grained material of low plasticity. 5.

Vent pipe - A 2" vent pipe, as obtained from Figure C-5, is recommended for all three outlet conduits.

6. Reinforced Concrete Quantities (from Table J-C1) Conduit size 20"

21" 24"

Type Steel R/C CMP

Concrete, cu yds 3.4 5.9 4.7

Reinforcing, lbs' 209 302 302 i

7. Hydraulic control - If the hydraulic control alternate (discussed in Section D) is used, no modification of the standard inlet structure (except size J ) is required other than to indicate embedded anchor bolts for the appropriate cylinder mount selected.

. TYPES OF GATE FRAME BACKS I

ALTERNATE LIFT DETAILS

FLAT BACK Shown mounted on "u" th~mble

ENCASED GEAR PEDESTAL L l F T

set in concrete wall. Anchor b o l t s are not required. This type of back may be mounted directly t o the concrete surface or bolted to a pipe flange.

This type of l i f t is required for a larger gate or higher head combination,

HYDRAULIC CYLINDER L l F T

I 1 111

seat facing

This type of l i f t is ordinarily mounted on a gate- yoke but can be mounted on the concrete surface in which the gate is set. The pump and valve for this l i f t may be located at the top of the embankment or at some other remote location not aligned with the gate axis.

I +I

/ SPIGOT BACK Shown cast in place in a concrete structure. This type of back may also be grouted into place i f proper recesses are provided. This type of back is also used when mounting a metal conduit.

PEDESTAL BASE HANDWHEEL L l F T This type of l i f t is normally used in a vertical position on an operating deck to raise the control wheel within reach of the operator.

HANDWHEEL L l F T This type of l i f t is similar to the pedestal base l i f , except it is mounted on an extension of the gate frame or onto an integral part of the structure.

FLANGE BACK Shown mounted directly on a concrete face. This type of back is used on gates operating at higher heads and may require a thimble mount.

THRUST BEARING YOKE Alternate hyd ~ l i ccylinder ir,sation in place of thrust bearing 2nd non-rising stem.

GATE FRAME Extend to support yoke.

FLANGE AND SPIGOT BACK Shown cast in place in a concrete structure. This type of back is used on gates operating at higher heads.

II

I I'

STEM Non rising, threaded a t gate.

it----

STEM

Rising, threaded a t l i f t

r

GATE FRAME STEM BLOCK

ANCHOR BOLT STEM BLOCK

Bronze wedge Bronze set

WEDGE BLOCK

wedge

GATE SLIDE SEATING SURFA CE C i r c u l a r or

WEDGE BLOCK Used in developing a watertight gate seal. Wedge blocks will also be located at top and bottom of gate i f gate is subjected t o unseating pressure.

~ c . Iframe .

r e c t a n g u l a r opening

NON-RISING STEM

I

RISING STEM

FIGURE C-l NOMENCLATURE WATER CONTROL GATE E W P Unit Portland, Oregon

Longt'tudinol stee / members /a

pI

11

bars

DETAILS

5 Conduit

PLAN

TRASH RACK

diam.

N o t to Scale

;I_ _f.

g'' r o d ,

When two intermediate bars o r e used space at @ .

ALT. ANCHOR BOLT

ANCHOR BOLT

-4 I--8" SECTIONAL ELEVATION

Note: When one intermediate bar is used place a t center.

STD. DWG. NO.

1

7- N - 2 0 4 6 5 (Suffixed by s i z e l e t t e r ) 2 sheets per each structure size

r*

W ~ o l u m eof concrete using C.M.P. o r steel pipe. and sizes o f p i p e .

See Table J - C I

f o r volumes using other types

0

lf p i p e d i a m e t e r is d i f f e r e n t f r o m that tabulated a d j u s t dimension 4 t h e i n l e t constant. (See discussion Section C- I V - A )

to keep the total height of

Example Given: Structure size G Head = 2 0 feet

Bar 4 x%

Bar 5 x +

l

51 10

4

I 9.5

5"

4"

rn

-,N

?0

Y

mI

m

m r n 3"

rn See AlSC S t e e l C o n s t r u c t ~ o nManual for Nomenclature

/

"?"

X

0

Ulr

0

-IN

-LN -w\ x

-

m . ( Y ( Y L

0

I

L

0

0

m 2'"2

-.

"Y RJ L

m z 2"

.

Find: With one intermediate cross b a r use line@ Longitudinal member = la'' pipe Cross,par A = 4 " x 53"; Cross bar B = 4" x i " Z = 4 With two interm iate cross bars use line Longitudinal member = I" pipe

Number of cross bars B

Cross bar A = 3 ' ' ~ ; ;Two cross bars B= 3''~;''

t = 3"

Structure size FIGURE C-2

INLET STRUCTURE EWP Unit Portland. Oregon

Note: Do not weld /ongitud/nal members to burs B.

or inlets larger than

bolt

SECTIONAL ELE

size E use sepwately removuble longitudinal members.

(-1" Dio anchor boll holes,

TRASH RACK FASTENING DETAILS PLAN Two Cross Bars

One Cross Bar $"r 8

Anchor bolt

Anchor

SECTION

rLv 1 " ~ i o onchor . bolt hole

'@

SECTION

@

See Figure C - 2 for dimensions not given on this f i g u r e .

ALTERNATE TRASH RACK DIMENSIONS

I

Example

END FASTENING DETAILS FOR "F" SIZE AND ABOVE STRUCTURES

TRASH RACK FASTENING DETAILS

Given.' Structure size G, head =201 Use one cross bur 8 F;nd: From figure C-2 longitudinal member = Cross bor 8 ; 4 ~ ; ' ;lengfh =3'0'' rf z 4" From figure C-3, ,, A =6'-a", 8 = z ~ / o ' : and bur spacing = 10.-c - c Use separately removable longitudinal members

FIGURE C - 3

ALTERNATE TRASH RACK E W P Unit Portland, Oregon

Thickness of rock riprop equols 1.5d7s. Thickness of filter equols 0 . 5 d 7 5 or 4" whichever is greoter.

P)

CE C

0

c 0

m 0

U V)

2

4 Rock riprap may be used in the shoded o r e 0 instead of the concrete slob.

+ Q,

a

-4-

I

fX 6

8

FIGURE C - 4

INLET PROTECTION EWP U n ~ tPortlond, Oregon

5

15

25

35

55

45

G a t e D i a m e t e r D or De - inches

Note .'

For rectongulor gates e n t e r chort with equivalent diameter (De)

Rectangular

Circular

FIGURE C- 5

VENT PIPE DIAMETER E W P Unit Portland, Oregon

SECTION D .CONTROLS

Page

Contents I

.

INTRODUCTION

.

DESCRIPTIONOFSYSTEMS

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

a

................. A . Mechanical . . . . . . . . . . . . . . . . . . . . . ..................... B . Hydraulic 1. C y l i n d e r . . . . . . . . . . . . . . . . . . . . 2 . Pump . . . . . . . . . . . . . . . . . . . . . . 3 . Reservoir . . . . . . . . . . . . . . . . . . . . 4 . Control v a l v e . . . . . . . . . . . . . . . . . . 5 . Hydraulic l i n e s . . . . . . . . . . . . . . . . . 6 . Hydraulic f l u i d . . . . . . . . . . . . . . . . . I11. COMPARISON . . . . . . . . . . . . . . . . . . . . . . . A. Mechanical System . . . . . . . . . . . . . . . . . . 1. Advantages . . . . . . . . . . . . . . . . . . . 2 . Disadvantages . . . . . . . . . . . . . . . . . . B . H y d r a u l i c System . . . . . . . . . . . . . . . . . . I . Advantages .................. 2 . Disadvantages ................. C . Labor Requirement ................. D . Motor Operated C o n t r o l s . . . . . . . . . . . . . . . E . Power v s . Manual Control O p e r a t i o n . . . . . . . . . I1

D- 1

D-1 D-1

D-2 D-3 D-3 D-3 D- 3

D-4

D-4 D-4

D-5 D-5 D-5 D-5 D-5 D-6 D-6 D-10 D-11

Contents (continued)

............ A . Mechanical C o n t r o l s . . . . . . . . . . . . . . . . . 1. L i f t P e d e s t a l S i z e . . . . . . . . . . . . . . . 2. Stem Diameter ................. 3 . L i f t Type ................... 4. Inlet Structure Size . . . . . . . . . . . . . . 5 . Stem P e d e s t a l S p a c i n g ............. B . Hydraulic Controls . . . . . . . . . . . . . . . . . 1 . C y l i n d e r Mount . . . . . . . . . . . . . . . . . 2 . Thrust . . . . . . . . . . . . . . . . . . . . . 3 . C y l i n d e r and Rod . . . . . . . . . . . . . . . . 4 . Reservoir ................... 5 . Pumps ..................... 6 . Valves . . . . . . . . . . . . . . . . . . . . . 7 . Tubing . . . . . . . . . . . . . . . . . . . . . 8. F l u i d ..................... V . DESIGNDETAILS . . . . . . . . . . . . . . . . . . . . . A . Mechanical System ................. 1. Gate Stem Encasement S e l e c t i o n C h a r t . F i g u r e D-2 ...... 2. Gate Stem D e t a i l s . F i g u r e s D .3. D-4 ......... 3 . Gate Stem P e d e s t a l . F i g u r e D-5 4 . Gate Stem Guide and Vent P i p e Hanger. FiguresD.6.D.7. D8. ............. ......... 5 . Gate L i f t P e d e s t a l . F i g u r e D-9 6 . Handwheel B r a c k e t and Base P l a t e . ............ F i g u r e s D.15. D.16. D-17 B . H y d r a u l i c System . . . . . . . . . . . . . . . . . .

IV

.

GATE CONTROL SELECTION PROCEDURE

Page

D-11 D-12 D-12

Contents (continued) Page

VI

.

VII

.

......................... SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . A . Sample M a t e r i a l S p e c i f i c a t i o n .H y d r a u l i c Con,t r o l s .

EXAMPLE

B

.

Sample C o n s t r u c t i o n S p e c i f i c a t i o n . I n s t a l l i n g H y d r a u l i c a l l y O p e r a t e d S l i d e Gates

.........

D-21 D-25 D-25

D-29

Figures

D-1 D-2

D-3

D-4

.............. Gate Stem Encasement S e l e c t i o n C h a r t . . . . . . . . . . Gate Stem D e t a i l s . . . . . . . . . . . . . . . . . . . . Encased Gate Stem D e t a i l s ............... Gate Stem P e d e s t a l . . . . . . . . . . . . . . . . . . .

Gate C o n t r o l S e l e c t i o n C h a r t

I1

II

1t

Handwheel B r a c k e t f o r Gate L i f t P e d e s t a l . S i z e s A & B

D-16

Base P l a t e f o r P e d e s t a l . S i z e C

D-17

Base P l a t e for P e d e s t a l s . S i z e s D

D-18

Gate L i f t P e d e s t a l s . S t e e l S c h e d u l e ."

It

11

D-37 D-39

.................. Size A . . . . . . . . . . . . . . .

D-15

D-19

D-35

.......

Adjustable S t e m G u i d e a n d V e n t P i p e H a n g e r

Gate L i f t P e d e s t a l s

D-33

II

II

..

...*........ & E .........

D-52 D-53

D-54 D-55

.

m

a

.

.

.

.

.

.

.

.

D-56

Figures (contirued) Page

D-20 D-21 D-22

D-23

D-24

.. ............ S e l e c t i o n C h a r t for H y d r a u l i c C y l i n d e r s . . . . . . . . . T y p i c a l D e t a i l s f o r H y d r a u l i c Cyl n d e r Gate C o n t r o l s . . Hydraulic Cylinder Interchange P a r t . . . . . . . . . . C o n t r o l O p e r a t i o n - Manual vs. P o w e r . . . . . . . . . .

Hydraulic Control Application

D-57 D-59

D-61

D-63 D-64

i

SECTION D

-

CONTROLS

INTRODUCTION Water storage reservoirs require outflow control to satisfy downstream water needs. The control system should be adjustable to a degree that waste is minimized, and should be able to retain its setting. The most common method of reservoir water control is the slide gate operated by means of a handwheel or geared crank lift. Support for the lift and the stem is provided by concrete pedestals set in the embankment. The hydraulic cylinder has been used a long time for slide gate control in water treatment plants. Recent advances in materials and production technology made the hydraulic system adaptable to many applications in earth dams. The Interchangeable Series of hydraulic cylinders of the Joint Industry Conference (JIC), available from several manufacturers, includes a wide range of sizes. A pressure range of 2000 psi operating, or 3000 psi non-shock, a variety of mounting styles of certain standard mounting dimensions, and several features that fill the requirements of Service installations are readily available. 11.

DESCRIPTION OF THE SYSTEMS

A.

Mechanical The mechanical system develops its lifting force from the principal of the screw. A handwheel or gear reduction unit, see Figure C-1, converts the effort of the operator on the handle to torque on the lift nut and thrust on the stem and the gate slide. The reaction to this thrust is taken by the mass of the gate lift pedestal and the embankment in which it is embedded. The thrust is transmitted to the gate by the stem, held in alignment by guides that are in turn secured to gate stem pedestals set in the embankment. If the basic structure is all concrete, the lift, guides, and gate frame are secured to it and all reactions are transmitted through it. Some manufacturers list a single maximum guide spacing for each stem size. The spacings shown on Figure D-1 are set by the allowable combined stresses in the stem material caused by the axial loading and bending from stem weight and eccentricity. Guides have several inches of vertical adjustment for correcting stem alignment as the embankment settles. Provisions for lateral adjustment are also included.

A v a r i a t i o n of t h i s s y s t e m , t h e n o n - r i s i n g stem model i s i l l u s t r a t e d i n F i g u r e C-1, i n which t h e l i f t n u t i s mounted i n t h e g a t e s l i d e and moves up o r down as t h e s t e m i s t u r n e d a t t h e c o n t r o l s t a t i o n . T h r u s t i s t a k e n by a b e a r i n g on t h e g a t e frame yoke and t h e l e n g t h o f s t e m from t h e c o n t r o l stat i o n t o t h e frame t r a n s m i t s t o r q u e o n l y . I n t h i s v a r i a t i o n t h e handwheel o r g e a r u n i t i s keyed t o t h e s t e m .

I n areas where f r e e z i n g i s a r e g u l a r w i n t e r o c c u r r e n c e , i t i s n e c e s s a r y t o e n c a s e t h e s t e m and b u r y i t t o a v o i d i t s b e i n g bound i n i c e o r f o r c e d o u t o f a l i g n m e n t . The encasement c o n s i s t s o f a p i p e f i l l e d w i t h o i l , equipped w i t h s e a l s a t e a c h end t o a l l o w t h e s t e m t o s l i d e f r e e l y t h r o u g h w h i l e r e t a i n i n g t h e o i l . Carbon s t e e l s t e m i s u s e d t h r o u g h o u t t h e encasement l e n g t h e x c e p t t h a t p o r t i o n which moves t h r o u g h t h e s e a l s . To m a i n t a i n a n e f f e c t i v e s e a l , t h e s e c t i o n of s t e m t h a t moves t h r o u g h t h e s e a l must remain c o r r o s i o n - f r e e and smooth, and i s made of b r o n z e o r s t a i n l e s s s t e e l . Even though t a b l e s i n d i c a t e t h a t a s m a l l e r s t e m of s t a i n l e s s s t e e l c o u l d r e p l a c e t h e r e g u l a r s i z e of c a r b o n s t e e l , i t i s n o t p r a c t i c a l ( c o n s i d e r i n g t h e n e c e s s a r y a d a p t i o n s ) t o change t h e s i z e f o r o n e s e c t i o n of t h e stem.

*

I f i t i s n e c e s s a r y t o u s e a b o l t e d s p l i c e i n s t e a d of t h e r i v e t e d one shown i n t h e s t a n d a r d d r a w i n g , i t w i l l a l s o be n e c e s s a r y t o i n c r e a s e t h e s i z e of encasement p i p e and t h e q u a n t i t y of o i l .

I n some c a s e s , a "TI' h a s been used i n t h e encasement n e a r t h e w e a t h e r s e a l f o r a d d i t i o n of o i l . T h i s d e t a i l h a s n o t been shown on t h e s t a n d a r d drawing s i n c e t h e w e a t h e r s e a l c a n be l o o s e n e d f o r t h e i n £ r e 4 u e n t need f o r more o i l . T h e r e a r e i n s t a n c e s where t h e u p p e r end o f a s t e m encasement h a s been c a s t i n t o t h e c o n c r e t e of t h e l i f t p e d e s t a l . Designs i n t h i s S e c t i o n c o n s i d e r t h a t no t h r u s t i s t o b e c a r r i e d i n t h e encasement p i p e . The s u p p o r t i n g a n g l e a t t h e l i f t pedest a l s e r v e s o n l y t o a i d a l i g n m e n t and t o r e l i e v e t h e p a c k i n g g l a n d o f s u p p o r t i n g t h e encasement w e i g h t . Any r e p a i r t o l i f t , stem o r g a t e t h a t w i l l r e q u i r e the' disassembly of t h e encasement w i l l show t h e a d v a n t a g e o f i n d e p e n d e n t c o n s t r u c tion.

B.

Hydraulic The muscle o f t h e h y d r a u l i c s y s t e m i s t h e d o u b l e - a c t i n g hydraul i c c y l i n d e r t h a t u s e s o i l under p r e s s u r e (up t o 3000 p s i ) t o move t h e p i s t o n and t h e a t t a c h e d g a t e s l i d e . P r e s s u r e i s d e v e l o p e d by a hand o r power o p e r a t e d pump a t t h e c o n t r o l s t a t i o n and developed by a hand o r power o p e r a t e d pump a t t h e

*

High c o s t of b r o n z e makes s t a i n l e s s a more e c o n o m i c a l c h o i c e .

\

control station and directed through piping to the opening or closing end of the cylinder by a 4-way valve. Typical Hydraulic Control Applications, Figure D-20, show variations in gate orientation that can be obtained without the usual alignment and access problems. The control station can be placed at. any convenient location within economic limits. Components are: Cylinder As stated earlier, a cylinder selected from the JLC Interchangeable Series can be supplied by several manufacturers. Certain options are necessary to meet the special needs of Service installations. Stainless steel piston rods are essential for submerged location. The exterior surfaces of.the cylinder should have corrosion protection of chrome, cadmium plating or an epoxy enamal. Packings for the piston and the rod gland must have maximum sealing characteristics to enable the piston to hold the gate in a raised position over a period of several days. A multiple-v type seal or a new cup type with an O-ring filler will give near zero leakage. The rod gland of these cylinders is replaceable without disassembling the whole cylinder. Pump Pressure to operate the cylinder is developed by a pump powered by hand, electric motor, or internal-combustion engine. There are several variations of pumps available that meet the minimum requirement for pressure. Hand pumps may be single or double acting, with dual pistons, adjustable leverage arrangements, or self-regulating devices to vary the flow rate when pressure requirements change. Rotary pumps for powered operation are usually of the gear, vane, or axial-piston type, listed in the ascending order of pressure capability. Reservoir An oil reservoir is necessary and should be located to keep the pump intake full at all times. Minimum reservoir capacity should be sufficient to contain the oil displaced by the cylinder piston rod when in the retracted (upper) position., Control Valve A 4-way valve directs the flow of oil from the pump to the opening or closing side of the cylinder piston and allows

return flow of oil to the reservoir. This valve may be a rotary or a spool type, either one further qualified as closed or open center.

A rotary-type selector valve effectively stops any back flow from the cylinder while in a neutral position, and maintains the set position of ,the gate. The spool-type valve, commonly used on hydraulic equipment,-has internal leakage inherent with its design and can allow the gate to creep closed over a period of time unless supplemented by a pilot-operated check valve at the cylinder. For hand-operated pump installations, a closed center valve is recommended. It will permit no through flow when the valve is in a neutral position. For power-operated systems, an open center valve is necessary to permit free return flow to the reservoir when the pump is idling.

5.

Hydraulic Lines

k

Pipe lines connecting the control station and the cylinder at the gate should be either stainless steel tubing or a rubber or synthetic hose suitable for medium or high pressure. In most cases they will be buried in the face of the embankment within a conduit of galvanized, fiber, or plastic pipe for external protection. Hose fittings should be corrosion resistant and of the permanent type, factory installed.

6. Hydraulic Fluid The hydraulic fluid is most commonly a mineral base oil with additives to maintain chemical stability, lubricating qualities, and anti-corrosion characteristics., Its viscosity should not exceed 3000 SSU (Saybolt second units) at the lowest expected operating temperature. This is to assure oil flow to the pump and lubrication during cold starting. This is most important to a powered unit. However, viscosity is an important factor in line loss due to friction and so affects hand units as well: COMPARISON

A choice between mechanical and hydraulic controls can be made by evaluating the advantages of the conditions for each system.

For

>

the usual situation, costs have been compared and the black dashed line on Figure D-1 represents the combination of head and gate size for which costs are about equal. Cost studies favor the mechanical system below the line and hydraulic above. The cost comparison assumes no stem is used in the hydraulic system and the cylinder is located at the gate. The advantages and disadvantages of the two control systems to be evaluated for a particular installation are:

A.

Mechanical System Advantages Simplicity of design. Economy in many sizes of gate-framelift units. Gates, lifts, and accessories are available from the same manufacturer. This factor is of more importance when it is necessary to place some responsibility for design with a subcontractor or supplier. Positive indication of the gate opening can be obtained. Portable gasoline or electric drives are available. Disadvantages The system needs careful alignment of all components. It is subject to misalignment with any settlement of the embankment. Broken slopes need special equipment, such as universal joints. Installations on vertical risers need access facilities such as catwalk or boat. Stop nuts are the only safety devices on standard units. Excess force on the handwheel or crank can damage the gate or the structure. Powered and automatic units with all safety devices are quite expensive. Labor efficiency is about 20%.

B.

Hydraulic System

1.

Advantages The gate may be oriented in any position without alignment with the control station. Broken slopes are no problem. The control station can be located anywhere (such as at the downstream measuring device) that can be reached with flexible conduit; convenience can be balanced with economy. Controls are easily adapted to power, remote, and automatic control. A multiple gate installation can be placed more compactly to use a common pump and power source. This system has an economic advantage in may slope installations or on risers that would otherwise require access facilities. Safety devices are easily incorporated into this system. Parts and service are available from local distributors. Labor efficiency is about 70%.

2.

Disadvantages There is a possibility of oil leakage. Positive indication of the gate opening is difficult. An approximation can be made with an oil level sight gage on the reservoir. Low temperatures can affect the speed of operation.

C.

Labor Requirement As a means of explaining and illustrating some of the principles involved in labor appraisal, the following example and explanation has been included. Given: A 30" x 30" gate under 40' differential head. Determine: Work required to open the gate by mechanical or hydraulic lift. Solution: The force required to move the gate is given by equation

where :

F

=

f

=

w h A G

= =

= =

total force required at the gate (lbs) coefficient of static friction between gate slide and seat density of water (62.4 lb/cu ft) unbalanced head of water on center of gate (ft) area of gate, including 1 inch seats (sq ft) weight of gate slide in air (lbs)

For a mechanical lift one manufacturer recommends a value of f = 0.3 for operation (relying on a momentary overload to overcome static friction, f = 0.7). The average weight of a 30" x 30" gate is 450 lbs. Substituting F

=

0.3

( 6 2 . 5 ) ( 4 0 ) (2.67)

+

4 5 0 = 5790 lbs

The manufacturer's selection is a geared crank lift with a 4 to 1 ratio and a stem diameter of 2 inches. The rating of the lift lists a capacity of 7540 lbs with 25 lb force on the crank, and 16 turns required per inch of gate movement. Efficiency of the lift is included in this catalogue rating.

S i n c e only 5790 l b s a r e needed, t h e r e q u i r e d f o r c e ( F ~ ) w i l l be propo&ional.

T o t a l work i s a p r o d u c t of f o r c e (F) and d i s t a n c e (D) o r

where:

W = t o t a l work ( i n - l b ) FR = f o r c e r e q u i r e d on c r a n k ( l b )

r = crank r a d i u s (inches) n = number of c r a n k t u r n s For one i n c h g a t e movement

W

= =

(19) (15) 2 7 (16) 28,700 i n - l b work i n p u t

For t h e same g a t e i n s t a l l e d w i t h a h y d r a u l i c c y l i n d e r l i f t t h e same m a n u f a c t u r e r r e q u i r e s 0.7 f o r a f r i c t i o n f a c t o r . The h i g h e r f o r c e f o r t h i s i n s t a l l a t i o n i s based on t h e concept t h a t t h e g a t e w i l l s e a t t i g h t e r and w i t h p u l s a t i n g o i l flow from a s i n g l e a c t i n g pump t h e g a t e w i l l i n t e r m i t t e n t l y s t o p and s t a r t . F

= = =

0.7(62.5)(40)(2.67)~ 12,480 12,930 l b s

+ 450 +

450

Chart 3 , F i g u r e D-21, g i v e s a c y l i n d e r of 3-1/4 i n c h d i a m e t e r with a standard p i s t o n rod. P i s t o n a r e a a v a i l a b l e f o r t h e opening s t r o k e i s 6.811 s q i n . The p r e s s u r e a t l e s s than 2000 p s i i s i n d i c a t e d by t h e shading b u t can be c a l c u l a t e d more e x a c t l y as f o l l o w s : F

P = x

-

12,930 l b s 6.811 i n 2

= 1900 p s i

where:

p = operating pressure (psi) F = t o t a l force (lbs) A = a r e a of p i s t o n Csq i n . )

The v a l u e o f p i s t h e p r e s s u r e r e q u i r e d a t t h e c y l i n d e r . L o s s e s i n moving t h e c o l d o i l t h r o u g h t h e t u b i n g w i l l r e q u i r e a d d i t i o n a l p r e s s u r e a t t h e pump. Assuming a v i s c o s i t y of 3000 SSU ( S a y b o l t second u n i t s ) a t a b o u t 30' F , a volume o f 0 . 1 g a l l o n p e r m i n u t e w i l l c a u s e a p r e s s u r e l o s s d r o p of 100 p s i p e r 100 f e e t o f 3/8 h o s e . The 40 f t head example w i l l r e q u i r e a b o u t 250 f t o f conn e c t i n g hose. p loss = 250 x 100 100 =

250 p s i

The o p e r a t i n g p r e s s u r e a t t h e pump w i l l t h e n b e t h e p r e s sure a t the cylinder + line loss, o r

+

p = 1900 250 = 2150 p s i

A common hand pump r a t e d up t o 3000 p s i may have a d i s placement of a b o u t 0 . 6 c u b i c i n c h e s f o r a f u l l s t r o k e . I n h y d r a u l i c t e r m s , work (W) i s d e f i n e d a s a p r o d u c t of p r e s s u r e (p) and volume ( v ) .

For one s t r o k e o f t h e example pump

w

= 2150

Ib

x 0.6 i n 3

in2 =

1290 i n - l b

The m e c h a n i c a l e q u i v a l e n t s o f t h i s amount of work a r e i l l u s t r a t e d i n t h e following sketch:

wr

pv

= /290in./b

-

To cylinder Pump

p v

= 2/50p s i = 0.6 cu i n

Mechanical E q u i v a l e n t s for f u l l piston stroke

6

If a comfortable stroke is assumed at 30 pounds through 25 inches, the useful piston displacement will be found by reversing the above process.

Hydraulic Equivalent for reasonable input

in"

- - 750 3 2150 in

where W,

force applied X distance (per stroke)

=

The number of strokes required to move the gate one inch is:

- 19.5 strokes inch

n A

=

v

=

=

number piston piston useful

of pump handle strokes area or volume per inch of cylinder movement pump piston displacement

The work a p p l i e d i n moving t h e g a t e one i n c h W = nW, = 1 9 . 5 x 750 i n - l b = 14,600 in-lb

For the example t h e m e c h a n i c a l l i f t r e q u i r e s 28,700 i n - l b o f work i n p u t t o a c c o m p l i s h 5 , 7 9 0 i n - l b of work o u t p u t . The e f f i c i e n c y i s t h e r a t i o . E f f = work o u t p u t work i n p u t =

5,790 in-lb 28,700 i n - l b

100

A s c a l c u l a t e d , c o n s i d e r i n g l o s s e s due t o o i l f l o w , t h e h y d r a u l i c s y s t e m r e q u i r e s 1 4 , 6 0 0 i n - l b of work t o accomp l i s h 12,930 i n - l b o f work o u t p u t e f f i c i e n c y f o r t h i s p a r t of t h e system i s ~

f

=f 12,930 i n - l b

100

14,600 in-lb

The e f f i c i e n c y o f a c y l i n d e r i s a b o u t 95-98% and t h e pump i s e s t i m a t e d a t 85% b a s e d on a l a r g e r r a t i o of f r i c t i o n s u r f a c e s and more m e c h a n i c a l l i n k a g e . The o v e r a l l e f f i c i e n c y o f t h e s y s t e m i s a p r o d u c t o f t h e s e three, or Eff

= =

0 . 8 8 x 0 . 9 5 x 0.85 x 100 71%

From t h e above t h e r e i s c o n s i d e r a b l e d i f f e r e n c e i n l a b o r between t h e two s y s t e m s which w i l l become even g r e a t e r i f t h e f r i c t i o n f a c t o r s s h o u l d b e c o n s i d e r e d more n e a r l y e q u a l . The d i f f e r e n c e becomes s i g n i f i c a n t when c o s t s a r e a s s i g n e d t o t h e l a b o r of o p e r a t i o n D..

Motor Operated C o n t r o l s Power d r i v e equipment s h o u l d i n c l u d e t h e f o l l o w i n g f e a t u r e s : Reverse

-

f o r opening o r c l o s i n g t h e g a t e .

Clutch - f o r q u i c k disengage e s p e c i a l l y i n e l e c t r i c m o t o r s of p o r t a b l e u n i t s .

Torque l i m i t

Adapter

-

-

p r e v e n t s o v e r l o a d when g a t e i s s e a t e d o r h i t s a submerged o b j e c t .

connects d r i v e u n i t t o l i f t control.

Gear r e d u c t i o n - p r o p e r r e d u c t i o n o f mocor s p e e d t o recommended g a t e s h a f t r e v o l u t i o n thru t h e l i f t control device. D r i v e equipment may b e p o r t a b l e and s e r v e s e v e r a l g a t e s o r may b e p e r m a n e n t l y i n s t a l l e d and s u i t a b l e f o r o u t d o o r o p e r a t i o n of a s i n g l e g a t e , a s i s n e c e s s a r y i n a u t o m a t i c operation. The d r i v e equipment may be g a s e n g i n e , e l e c t r i c , o r a g a s e n g i n e o p e r a t e d g e n e r a t o r f o r a n e l e c t r i c motor. Manual c o n t r o l s i z e and g e a r r a t i o a r e s e l e c t e d n o t t o exceed man's c a p a c i t y t o t u r n a c r a n k . The need f o r a motor t o o p e r a t e t h e c o n t r o l s w i l l depend p r i m a r i l y on Small t h e allowable time l i m i t f o r r e s e t t i n g t h e gate. g a t e s would n o r m a l l y n o t r e q u i r e power o p e r a t i o n . The l a r g e r g a t e s could r e q u i r e motorized l i f t s i f t h e g a t e i s t o b e moved o v e r i t s f u l l h e i g h t , however seldom w i l l t h e g a t e b e f u l l y opened o r c l o s e d a g a i n s t a f u l l head a t any one t i m e . A t y p i c a l i r r i g a t i o n s e a s o n might b e g i n w i t h 112 of t h e d e s i g n f l o w , r e q u i r i n g 114 opening o f t h e g a t e with a f u l l reservoir. Flow changes t h r o u g h o u t t h e s e a s o n r e q u i r e minor a d j u s t m e n t s o f t h e g a t e . A t 314 way t h r o u g h t h e s e a s o n , f u l l f l o w might be o b t a i n e d w i t h 318 g a t e openi n g and a b o u t 1 1 2 o f f u l l head. For emergency g a t e c l o s u r e p r o b a b l y n o t more t h a n 114 t o 1 1 3 o f t h e e f f o r t r e q u i r e d t o move t h e g a t e f o r i t s e n t i r e d i a m e t e r a t f u l l r e s e r v o i r w i l l be needed. E.

Power v s Manual C o n t r o l O p e r a t i o n F i g u r e D-24 h a s been developed f o r c a l c u l a t i n g e f f o r t r e quired t o operate the controls. I n t h i s figure, present day manpower c a p a b i l i t y h a s b e e n a s s e s s e d i n t e r m s of f r a c t i o n a l horsepower. Entering with the required force i n t h e a p p r o p r i a t e system ( h y d r a u l i c o r m e c h a n i c a l ) move t o the i n t e r s e c t i o n with t h e desired gate t r a v e l , follow t h e 45O g u i d e l i n e down t o t h e p o i n t of i n t e r s e c t i o n f o r t h e l i m i t i n g t i m e f o r o p e r a t i o n , move h o r i z o n t a l l y t o r e a d horsepower and i n t e n s i t y of p h y s i c a l e f f o r t .

IV.

GATE CONTROL SELECTION PROCEDURE

Once t h e g a t e s i z e h a s b e e n d e t e r m i n e d , t h e s e l e c t i o n of t h e g a t e c o n t r o l s i s c o m p l i c a t e d and y e t f a i r l y s i m p l e . P a r t of t h e

c o m p l i c a t i o n l i e s i n t h e v a r i e t y of c a t a l o g u e equipment and e n g i n e e r i n g d a t a a v a i l a b l e from t h e s e v e r a l s u p p l i e r s i n t h e a r e a . Reducing t h e number of component c h o i c e s t o t h o s e a v a i l a b l e from s e v e r a l s u p p l i e r s and s t a n d a r d i z i n g t h e a p p u r t e n a n c e s s i m p l i f i e s t h e s e l e c t i o n procedure.

The v e r t i c a l s c a l e a t t h e l e f t edge o f F i g u r e D - 1 w i l l n o r m a l l y b e t h e maximum head on t h e g a t e . Even w i t h a n e x t e n d e d p i p e l i n e on a s t e e p s l o p e v e r y l i t t l e a d d i t i o n a l head w i l l b e d e v e l o p e d below t h e g a t e p r o v i d e d t h e s y s t e m i s v e n t e d a s recommended i n Except f o r u n u s u a l s i t u a t i o n s t h e head on t h e s y s t e m F i g u r e C-5. i s measured from g a t e c e n t e r l i n e t o f r e e w a t e r s u r f a c e . Two h o r i z o n t a l s c a l e s i m m e d i a t e l y below t h e body o f t h e c h a r t l i s t t h e a d d i t i o n a l information normally r e q u i r e d b e f o r e t h e system can b e d e s i g n e d . Emphasis must be p l a c e d on t h e f a c t t h a t w h i l e t h e c o n d u i t s i z e and g a t e s i z e may be t h e same, t h e l o a d i s exe r t e d o v e r a g r e a t e r a r e a b e c a u s e of t h e g a t e s e a t s . Adding 3 i n c h e s t o t h e g a t e d i a m e t e r w i l l b e s u f f i c i e n t f o r most g a t e models t o a l l o w f o r t h e e x t r a a r e a o v e r which t h e w a t e r p r e s s u r e c a n b e a p p l i e d . A word o f c a t i o n : A CIRCULAR CONDUIT MAY HAVE A GATE WITH SEAT FACINGS SET I N A RECTANGULAR PATTERN THAT MATERIALLY INCREASES THE LOAD ON THE CONTROL SYSTEM. I n t h i s case, a r e c t a n g u l a r a r e a i n c l u d i n g g a t e s e a t s s h o u l d b e used i n c a l c u l a t i n g r e s i s t i n g force. A.

Mechanical C o n t r o l s The t o t a l l o a d t o b e h a n d l e d by t h e components of a g a t e cont r o l s y s t e m v a r i e s w i t h t h e s i z e o f g a t e and head of w a t e r . A s e r i e s of d i a g o n a l l y c u r v e d l i n e s on F i g u r e D-1 e x p r e s s e s t h e v a r i a t i o n of l o a d d i r e c t l y i n t o component s i z e r e q u i r e ments r a t h e r t h a n i n pounds. S i n c e t h e s t e m d i a m e t e r , t h e l i f t and i t s p e d e s t a l a r e s i z e d f o r t h i s common l o a d , t h e i r s e l e c t i o n h a s b e e n i n c o r p o r a t e d i n t o t h i s one f i g u r e .

1.

L i f t Pedestal Size The uppermost s c a l e o f F i g u r e D-1 i s d i v i d e d i n t o s i x zones, A t h r u F, r e p r e s e n t i n g s t a n d a r d i z e d l i f t p e d e s t a l s i z e s and t h e r a n g e o f l o a d ( g a t e s i z e v s h e a d ) f o r which t h e y were d e v e l o p e d . Zone l i m i t s have been e x t e n d e d i n t o t h e body of t h e f i g u r e by t h e s o l i d b l a c k d i a g o n a l l y curved l i n e s . D e t a i l s f o r t h e l i f t p e d e s t a l a r e found on F i g u r e s D-9 t h r u 1 4 and i n t h e Appendix, T a b l e J-D2.

2.

Stem Diameter The second s c a l e a c r o s s t h e t o p o f F i g u r e D-1 i s d i v i d e d i n t o t h r e e r e d a r e a s e x t e n d i n g i n t o t h e body of t h e f i g u r e .

f

-

These s e p a r a t e t h e f i g u r e i n t o f i v e zones d e l i n e a t i n g t h e r a n g e o f l o a d t h a t may be h a n d l e d by t h e stem d i a m e t e r s l i s t e d a c r o s s t h e f i g u r e . The d i a m e t e r s have b e e n l i m i t e d t o t h o s e r e a d i l y a v a i l a b l e from most g a t e s u p p l i e r s . L i f t Type The t h i r d s c a l e on F i g u r e D - 1 p e r t a i n s t o l i f t t y p e . For l a r g e r g a t e s and h i g h e r h e a d s t h e l o a d i s heavy enough s o t h a t geared crank l i f t s a r e r e q u i r e d . T h i s zone i s shown w i t h a b l a c k background and i s d i v i d e d i n t o t h r e e g e a r r a t i o s . For s m a l l e r g a t e s and h e a d s , an o p e r a t o r can h a n d l e t h e l o a d w i t h a l e s s e x p e n s i v e handwheel v a r y i n g i n s i z e from 10" t o 30" d i a m e t e r s l i s t e d a c r o s s t h e s c a l e . A s t h e l o a d becomes g r e a t e r a t t h e r i g h t end of t h e handwheel s c a l e , b a l l b e a r i n g s a r e r e q u i r e d t o r e d u c e f r i c t i o n and c o n s e q u e n t l y , t h e p u l l t h a t t h e o p e r a t o r h a s t o e x e r t on t h e handwheel t o move t h e g a t e . Both handwheel and g e a r e d c r a n k l i f t a r e s i z e d s o t h a t t h e maximum p u l l t h e o p e r a t o r h a s t o e x e r t i s 40 l b s . A b r o n z e lift n u t w i l l r e d u c e f r i c t i o n and t h e r e q u i r e d p u l l t o a b o u t 35 l b s maximum and i s recommended f o r t h o s e i n s t a l l a t i o n s t h a t r e q u i r e frequent gate adjustment. Inlet Structure Size

Its The i n l e t s t r u c t u r e s i z e i s n o t shown on t h i s s h e e t . s i z e i s dependent o n l y on t h e c o n d u i t . The a p p r o p r i a t e l e t t e r d e s i g n a t i o n may b e found on F i g u r e C-2. Stem P e d e s t a l S p a c i n g The d i a g o n a l l i n e s l a n t i n g upward toward t h e r i g h t a c r o s s t h e c h a r t g i v e s recommended s p a c i n g o f t h e g a t e s t e m supports. Encased s t e m s The d i m e n s i o n s j u s t above t h e l i n e a r e f o r e n c a s e d stems which s h o u l d be used i n a r e a s s u b j e c t t o f r e e z i n g o r where t h e s t e m s a r e t o be b u r i e d i n r o c k r i p r a p . Unencased s t e m s Below t h e d i a g o n a l l i n e , s u p p o r t s p a c i n g s a r e l i s t e d f o r unencased s t e m s t o b e u s e d i n g e o g r a p h i c a r e a s n o t s u b j e c t t o f r e e z i n g . Unencased stems c a n n o t be b u r i e d . When t h e d i s t a n c e between s u p p o r t s becomes s m a l l e r , a n e n c a s e d s t e m becomes c h e a p e r . A reminder

i

of this fact is indicated on this figure and in the previous discussion of Figure D-2. Obviously the comparison should be made only when the unencased stem might be used. B.

Hydraulic Controls The cost of stem controlled gates varies directly with gate size and also with head. At some combination of head-gate diameter, the cost of hydraulic controls becomes cheaper than the stem control. A black dashed diagonal line curving downward to the right across the face of the chart delineates approximately a break-even point between the two systems. Comparison between the two control systems was discussed in 11, DESCRIPTION OF SYSTEMS. Anchorage requirements and selection of two components for the hydraulic system is simplified by the "Selection Chart for Hydraulic Cylinders", Figure D-21. The following are components or considerations that require evaluation in a hydraulic system:

I. Cylinder Mount S

Before the actual cylinder size is determined the type of cylinder mount should be selected. Structure type and gate details are factors in this selection. Several types of mounts for typical applications are shown on Figures D-20 and D-22.

2.

4,-

Thrust Enter Chart I (Figure D-21) with head on the gate and gate area (including allowance for gate seats). From the intersection of lines projected from these values move downward to the right parallel to the 45' guide lines to Chart 2. When the extended line reaches the point corresponding to the weight of ,the gate slide, turn horizontally to right and read thrust on cylinder mount. This thrust is the maximum force required to overcome static friction between gate seats and the pull of gravity on the slide.

3. Cylinder and Rod From the thrust value, continue horizontally into Chart 3 to intersection with a vertical line projected from the value of "L" at the bottom of the chart. "L" shown schematically in the diagram in the upper right corner of Figure D-21 is the unsupported length of the rod and depends on the location of the cylinder mount.

I

Chart 3 is divided into 14 irregular shaped zones defined by the heavy black lines and labeled witk a cylinder bore size enclosed in a circle. Beside each bore 3ize is the area of the piston that is effective in the pull or retracting stroke. The abbreviation Std or Q.S. following the area indicates whether the piston rod is standard or oversize. Each zone is divided into two areas: the red area represents pressures between 2000 and 3000 psi with the higher values at the top of the area; the white area represents pressures below 2000 psi.

A point on Chart 3 for a combination of thrust and distance (L) determines the cylinder requirements: pressure (greater or less than 2000), bore, and rod type (standard or oversize).

4. Reservoir Minimum reservoir capacity for oil storage is the volume of the cylinder less that displaced by the piston and rod. Displacement of an oversize rod is greater than that for the standard rod. Chart 4 of Figure D-21 takes this in account by providing two vertical scales for a given cylinder bore size. The horizontal scale of Chart 4 is graduated for values of stroke which is the distance the piston must move to open the gate slide to clear the opening, usually gate diameter plus 3 inches. Having determined the cylinder and stroke requirements, an intersection of lines projected from these values will establish a point on Chart 4 from which reservoir capacity can be interpolated. A standard reservoir of this size or larger is required to keep the pump full.

5. Pumps Every hydraulic alone, or as an ment is simple: cylinder with a of flow will be

gate control system will have a hand pump, auxiliary to a powered unit. The requireto develop the required presqure in the reasonable force on the handle. The rate dependent on the operator.

The pump for a powered installation will be selected according to pressure requirement of the system, about as follows:Pressure Required

Pump Type

to 1200-1500 psi to 2000-2500 psi to 2000-3000 psi

gear vane axial-piston

E l e c t r i c power i s i f i t is r e l i a b l e A gasoline engine type should d r i v e Details.

6.

more c o n v e n i e n t t o c o n t r o l and economical and a v a i l a b l e c l o s e t o t h e i n s t a l l a t i o n . c a n be a d a p t e d t o any l o c a t i o n . E i t h e r t h e pump a t t h e p r o p e r s p e e d . S e e Design

Valves

A four-way r o t a r y - t y p e s e l e c t o r v a l v e w i l l p r o v i d e t h e r e q u i r e d c o n t r o l and s e a l i n g c h a r a c t e r i s t i c s f o r t h e m a j o r i t y of SCS i n s t a l l a t i o n s . P o r t s i z e s w i l l depend on the t u b i n g t o b e u s e d . O t h e r c h o i c e s a r e concerned w i t h t h e t y p e of c i r c u l a t i o n p a t t e r n s . For C o n d i t i o n s

7.

Handpowered s y s t e m single cylinder

-

use closed-center

Powered s y s t e m s i n g l e cylinder

-

use open-center t o a l l o w f o r f r e e o i l r e t u r n t o tank

Powered s y s t e m multiple cylinder

- use closed-center

valves with pilot-operated r e l i e f v a l v e a s by-pass

Tubing The b a s i c r e q u i r e m e n t s of t u b i n g a r e ( 1 ) t o c o n t a i n maximum working p r e s s u r e , ( 2 ) t o p a s s t h e r e q u i r e d f l o w w i t h r e a s o n a b l e f r i c t i o n l o s s , and ( 3 ) t o resist t h e e n v i r o n m e n t a l c o n d i t i o n s i n which i t must b e p l a c e d . The f o l l o w i n g a r e guides f o r t h i s s e l e c t i o n : For C o n d i t i o n s Enclosed

-

above w a t e r

Exposed t o w e a t h e r

Conduit e n c l o s e d (submerged) Direct burial (submerged)

-

u s e carbon s t e e l t u b i n g or - use carbon s t e e l t u b i n g (plated o r coated) or - u s e p r e s s u r e hose SAE (lOOR1 o r 100R2)

- use s t a i n l e s s s t e e l

R e f e r t o m a n u f a c t u r e r s ' c a t a l o g s f o r p r e s s u r e r a t i n g s of tubing o r hose i n d i f f e r e n t s i z e s .

8.

Fluid The hydraulic fluid should be selected on the recommendations of the component manufacturers for the conditions of climate and exposure in the vicinity of the installation.

V.

DESIGN DETAILS

A.

Mechanical System Several of the necessary accessories to a mechanical. system are described in the following figures and illustrated at such a scale that they may be traced full size or assembled with other selected details for photographic reproduction, as described in Section H. 1.

Gate Stem Encasement Selection Chart, Figure D-2 Figure D-2 is of value only where an unencased stem is being given serious consideration. Omitting the encasement results in economy only when the pedestal spacing exceeds some limiting dimension. Entering Figure D-2 with the unencased stem spacing obtained from Figure D-1 and moving vertically till it intersects the selected stem diameter will provide a rapid answer. An intersection in the unshaded zone indicates an unencased stem is cheaper; in the shaded zone, the encased stem is cheaper. Approximate costs per foot of stem for either type installation may be taken from this chart. The line forming the boundary between the shaded and unshaded areas pertains to the encased stem. Its intersection with the stem diameter lines approximates the construction cost. For the unencased stem, intersection of the pedestal spacing with the stem diameter regardless of the zone it is in approximates the construction cost.

2.

Gate Stem Details, Figures D-3, D-4 Figures D-3 and D-4, Gate Stem Details, pictures the typical installations of.encased gate stems and details of splices for both types. D-3 details are used on drawings that are to be reduced for reproduction. D-4 details are of a suitable scale for direct use on,drawings to be used full size. The table on D-3 contains dimensions and other values necessary to complete the details in either scale.

3.

G a t e Stem P e d e s t a l , F i g u r e D-5 F i g u r e D-5, G a t e Stem P e d e s t a l , i l l u s t r a t e s t h e recommended p e d e s t a l f o r s u p p o r t of any s i z e g a t e s t e m a t any s p a c i n g . E i t h e r of t h r e e g u i d e s may b e u s e d as shown i n F i g u r e s D-6, D-7 o r D-8. A s n o t e d on t h e d r a w i n g s , r i p r a p s h o u l d n o t c o v e r a n unencased stem.

4.

Gate Stem Guide and Vent P i p e Hanger, F i g u r e s D-6,

D-7,

D-8

F i g u r e s D-6, D-7 and D-8, Gate Stem Guide and Vent P i p e Hanger, show t h r e e d e v i c e s f o r mounting g a t e s t e m t o pedestals. D-6 u s e s s t a n d a r d U-bolts and c h a n n e l s e c t i o n and r e q u i r e s no welding. D-7 u s e s s t e e l b a r s b e n t and d r i l l e d t o s u p p o r t t h e s t e m , encasement and v e n t p i p e . D-8 i l l u s t r a t e s a s t e m g u i d e t y p i c a l o f t h o s e s u p p l i e d by g a t e m a n u f a c t u r e r s , u s u a l l y of c a s t i r o n , and a v a i l a b l e w i t h bronze bushings a s an o p t i o n . T h i s t y p e is designed t o f i t c l o s e l y t o a g a t e s t e m and o r d i n a r i l y i s n o t i n tended f o r u s e w i t h encasement. 5.

[

Gate L i f t P e d e s t a l , F i g u r e D-9 F i g u r e D-9, G a t e L i f t P e d e s t a l s , p r o v i d e s o u t l i n e dimens i o n s and q u a n t i t i e s f o r t h e s i z e s A t h r o u g h E r e f e r r e d from F i g u r e D-1. Drawings 7-L-20544 (A-.E) l i s t e d i n t h e t a b l e t i o n d e t a i l s i n c l u d i n g r e i n f o r c i n g steel f o r and a r e i n c l u d e d on F i g u r e s D-10 t h r u D-14. and E t h e c r a n k s a r e o r i e n t e d t o r e q u i r e t h e o r bending of t h e o p e r a t o r .

6.

show c o n s t r u c each s i z e On s i z e d D least stooping

Handwheel B r a c k e t and Base P l a t e , F i g u r e s D-15,

D-16,

D-17

F i g u r e D-15 t h r u D-17, Handwheel B r a c k e t Base P l a t e , g i v e d e t a i l e d d i m e n s i o n s f o r f a b r i c a t i o n o f b r a c k e t s and b a s e p l a t e s f o r mounting l i f t s on p e d e s t a l s .

B.

H y d r a u l i c System Some d e t a i l s of i n s t a l l a t i o n t h a t d i f f e r from a m e c h a n i c a l s y s t e m a r e shown i n F i g u r e D-22, T y p i c a l D e t a i l s . I t i s most i m p o r t a n t t o n o t e t h e r e l a t i o n s h i p s o f dimensions Eg and Ey

t o make a s e c u r e f a s t e n i n g t o t h e g a t e s l i d e and t o p r o v i d e a d e q u a t e c l e a r a n c e f o r s l i d e and frame i n a l l p a r t s o f t h e o p e r a t i n g c y c l e . M o d i f i c a t i o n of t h e stem b l o c k i s needed t o permit t h r e a d i n g t h e block t o t h e p i s t o n rod without turning t h e piston i n t h e cylinder o r turning t h e cylinder i t s e l f . The wrench f l a t s a r e l o c a t e d (dimension Eg) s o a s t o be a c c e s s i b l e f o r holding t h e rod during t h e e n t i r e threading operation. The s i m p l e s t i n s t a l l a t i o n u s e s a f l a n g e mount c y l i n d e r a t t a c h e d t o a yoke on t h e g a t e frame. T h i s assembly c a n b e f a b r i c a t e d , assembled and t e s t e d u n d e r shop c o n d i t i o n s b e f o r e f i e l d i n s t a l l a t i o n . A s i d e f o o t mount i s a p p l i c a b l e i n many c a s e s b u t a n c h o r b o l t s must b e l o c a t e d c a r e f u l l y t o a v o i d d i f f i c u l t f i e l d adjustments. A s t e e l p l a t e , s l o t t e d f o r t h e anchor b o l t s , s e r v e a s an i n t e r m e d i a t e a d j u s t a b l e mounting on which t o b o l t t h i s t y p e c y l i n d e r . A t h i r d method, u s i n g t h e t r u n n i o n mount, h a s b u i l t - i n f l e x i b i l i t y i n o n e p l a n e of movement and c a n b e used t o a d v a n t a g e i n s p e c i a l s i t u a t i o n s , ( l i m i t e d h e a d room) as i l l u s t r a t e d . S a f e t y devices f o r t h e system i t s e l f a r e suggested i n the following order:

1.

A p r e s s u r e g a g e , marked w i t h t h e d e s i g n o p e n i n g and c l o s i n g p r e s s u r e s , w i l l b e s u f f i c i e n t f o r a handpowered s y s t e m and competent o p e r a t o r .

2.

P r e s s u r e r e l i e f v a l v e s , s e t f o r design opening o r cl-osing p r e s s u r e s and p l a c e d i n t h e r e s p e c t i v e s i d e o f t h e c i r c u i t , g u a r d a g a i n s t e x c e s s p r e s s u r e s a p p l i e d by unknowing o r u n a u t h o r i z e d hand o p e r a t o r s o r a n u n a t t e n d e d power u n i t .

3.

A t r a v e l l i m i t c i r c u i t allows o i l t o bypass t h e c y l i n d e r when t h e g a t e i s c o m p l e t e l y open o r c l o s e d and e l i m i n a t e s t h e c o n t i n u o u s blowoff o f t h e r e l i e f v a l v e s i f a powered u n i t i s n o t c o n t i n u o u s l y watched d u r i n g o p e r a t i o n .

For a power i n s t a l l a t i o n , a d d i t i o n a l c a l c u l a t i o n s a r e r e q u i r e d . The power r e q u i r e m e n t i s s e t by t h e amount o f work and t h e time allowed. From t h e p r e v i o u s example of a 30" x 30" g a t e , t h e work f o r o n e i n c h of g a t e movement was 1 4 , 6 0 0 i n c h pounds. Assuming a maximum a l l o w a b l e t i m e f o r o p e n i n g of 5 m i n u t e s , t h e power i s found i n t h i s manner:

Work Time (14,600 i n - l b ) (I2

(in)

(32 i n . )

(5 min) (33,000 f t - l b ) min HP

0.236 HP The o i l flow requirement of t h e system f o r opening t h e g a t e is : vol

(6.811 i n 2 ) (32 i n . ) (5 min) = 43.6 cu i n . p e r minute

A t y p i c a l pump f o r such a n i n s t a l l a t i o n w i l l d e l i v e r about 1 . 2 c u b i c i n c h e s of o i l p e r r e v o l u t i o n . The r e q u i r e d speed of t h e pump i s t h e n : Rev = (43.6 i n 3 ) 3 (1.2 in) rev =

36.4 r e v o l u t i o n s p e r minute

An e l e c t r i c motor of 114 o r 1 / 3 BP r a t i n g should b e a d e q u a t e f o r t h i s i n t e r m i t t e n t u s e . The common motor speed of 1 , 7 6 0 rpm must be reduced t o t h e 36 rpm of t h e pump by g e a r , c h a i n o r b e l t d r i v e . Without speed r e d u c t i o n t h e pump would a t t e m p t i t s f u l l o u t p u t a g a i n s t t h e o p e r a t i n g p r e s s u r e of t h e c y l i n d e r r e s u l t i n g i n an o v e r l o a d on t h e power u n i t .

The remote l o c a t i o n of most r e s e r v o i r s s u g g e s t s t h e u s e o f a g a s o l i n e e n g i n e . The u s u a l p r o c e d u r e f o r s e l k c t i n g a g a s o l i n e e n g i n e i s t o r e q u i r e 50% more power t h a n t h e l o a d . For t h e example, however, t h e r e a r e few c h o i c e s a v a i l a b l e l e s s t h a n A s w i t h t h e e l e c t r i c motor, t h e speed must b e a b o u t 2 HP. reduced t o t h e speed of t h e pump. When a hand pump i s used a s a n a u x i l i a r y t o a powered pump, i t must be i n s t a l l e d p a r a l l e l t o t h e powered pump and t h e d i s c h a r g e l i n e of each guarded by a check v a l v e a g a i n s t backflow induced by t h e o t h e r u n i t . I d e a l l y t h e c o n t r o l s t a t i o n c i r c u i t r y and t h e c y l i n d e r assembly a t t h e g a t e s h o u l d b e shop assembled by workmen w i t h h y d r a u l i c s equipment e x p e r i e n c e . Both a s s e m b l i e s can t h e n be t e s t e d and a d j u s t e d under shop c o n d i t i o n s . Quick c o u p l e r s might b e used f o r t h e f i n a l c o n n e c t i o n s reducing much of t h e

mess and the hazard of contamination usually attendant with field assembly. This approach to the installation process should result in compact,.neat assemblies, fully tested and ready for service. Sample specifications for the usual items of hydraulic equipment are included in Section VII as a guide for bid preparation.

VI .

EXAMPLE Continuing the example of the previous sections, the following procedure illustrates the selection of additional details required on the construction drawings. This example assumes the drawings will be reduced from "E" size (21 x 30) to "L" size (10 1/2" x 15"). This example in detail selection is restricted to the mechanical system of controls since no standard details have been developed for the hydraulic alternate. Given: The earth dam example of Section B, with choices of 20" steel pipe, 21" R/C pipe or 24" CMP, and a head of 20 ft. Determine: The size of the gate control components for each of the three pipe sizes and details for the construction drawings. Problem Analysis :

1. Find stem diameter required. 2. Find stem pedestal spacing required. 3. Find lift pedestal size required. 4. Find lift type required. 5. Find vent pipe size required. 6. Determine construction drawing details. 7. Find requirements of an alternate hydraulic control system for comparison with the mechanical system, Solution: 1.

Since a stock gate is available for each of the conduit sizes, three solutions are possible. Enter Figure D-1 with the conduit diameter plus three inches and a 20'-0" depth of water to gate centerline.

2.

The inlet structure size was selected in Section C. The rest of the components tabulated below can be obtained from Figure D-1.

Conduit Dia Conduit dia

f

20" Steel

3"

Inlet structure size Stem diameter Stem pedestal spacing Encased Unencased Lift pedestal size Lift type Alternate hydraulic control 3.

24" CMP

16'-0" 10'-6" C 30" handwheel

consider

16'-0" 10'-6" C 24" handwheel (ball bearing) consider

16'-0" 10' -0" C 30" handwheel (ball bearing) consider

In the mechanical system the only alternate choice is between the encased and unencased stem. The encased stem is selected because of icing conditions and burial of the stem in rock riprap placed on the embankment for erosion protection. For the remainder of the control details, select the following common to all three pipe sizes: Gate stem details Gate stem pedestal Gate stem guide Lift pedestal Concrete quantity and Std Dwg No Base plate detail

Figure D-3 " D-5 " D-6

Circled blanks on Figure D-3 indicate information that is to be filled in. The stem diameter was previously found to be 1 112". The following related information is found on Figure D-3.

a.

Stem splice

1 1/2" x 9" heavy wall seamless steel

b. c. d.

Rivets Encasement Oil

tubing 2 - 5/8 x 3" 2 1/2" standard galvanized pipe 0.627 qts of SAE 20 motor oil per foot of encasement

On Figure D-6, in addition to the information related to the stem diameter listed on the same figure, a 2" vent pipe was found required for this job from Figure C-6.

4.

The procedure for selecting the alternate hydraulic controls is presented using the 24" CMP pipe from the previous example.

Assume a 24" rectangular gate weighing approximately 200i1, average for this type of gate. a.

Enter Figure D-21 with the area ~nclosedby the gate seats (24 + 3)(24 + 3) = 5.06 ft and H = 20 ft and find the intersection point. From this point move diagonally down to the right along the 45' grid to about 200# gate weight, Move horizontally from this point to find 4700# thrust.

b.

The required stroke is 24 + 4 = 28". Using a front end cylinder mount the unsupported rod length, L, is 28" plus extra length required by the gate slide frame. This extra distance according to the catalogues reviewed is about 114 the gate size. Therefore, using 6" plus 2" for clearance at the cylinder support the total unsupported rod length is then 28 + 6 + 2 = 36".

c.

Enter F.igure D-21, Chart 3 with thrust = 4700 lbs and and find a 2" bore with an oversize rod. Also find operating pressure in the 2000 to 3000 psi zone.

L = 36"

d.

Enter Figure D-21, Chart 4 using the 28" stroke and a 2" cylinder bore size with an oversized rod and find the required reservoir capacity of 50 cubic inches.

e.

Using Figure D-23 and requiring a front trunnion mount, the following cylinder makes and models can be used: 1. 2. 3.

Carter model no. ENS Hannifin model no. D-HI0 Miller model no. H81

f.

The example installation can be easily operated by a hand pump. For the 3000 psi requirement, select a pump with about a 314 in. piston. Displacement for each comfortable stroke will be about 0.25 cu in. and about 6.5 strokes will move the gate up one inch. Several pumps meeting these requirements are obtainable with integral reservoirs that are equal to or greater than the minimum capacity requirement of 45 cu in.

g.

Assuming that the hydraulic lines are to be buried separately from the air vent, stainless steel is the required material. 114 inch diameter would carry the required flow of oil but 3/8 inch will probably justify its extra cost in effort saved. Wall thickness should be 0.028 inches.

h.

Select a four-way rotary selector valve ported for 318 tubing. For this hand-powered installation a closed center will give the desired circulation pattern.

VZI.

SAMPLE MATERIAL SPECIFICATION A.

Hydraulic Controls

SAMPLE MATERIAL SPECIFICATION 310.

HYDRAULIC CONTROLS

This specification covers the quality of hydraulic controls for slide gates.

GENERAL REQUIREMENTS The hydraulic controls, including cylinder, pump, valves, lines and fittings, shall conform to the requirements of the Joint Industry Conference (JIC) Hydraulic Standards for Industrial Equipment, Revised April 1959. CYLINDER The cylinder shall be selected from the JIC Interchangeable Series rated for 2000 psi operating or 3000 psi non-shock loading. The piston rod shall be stainless steel with threads and wrench flats machined as required to meet mounting requirements as shown on the drawings. Seals for the piston and the rod bearing shall be the multiple-V type or shall have equivalent sealing characteristics. A metallic external wiping ring shall be incorporated with the rod bearing.

A hand operated pump shall be capable of developing the design pressure with not more than 60 pounds force on the handle. It shall be equipped with a check valve to prevent backflow between power strokes.

A pump for use with engine or electric motor drive shall deliver oil at the specified rate and pressure without overload on the power unit. The pump and power unit shall be aligned so that bearing loads, stresses in connecting elements and losses due to friction are no greater than for normal power transmission. RESERVOIR

A reservoir shall be supplied with capacity as specified or shown in the drawings.

Provision shall be made for filtering the

h y d r a u l i c f l u i d during f i l l i n g . Piping f o r t h e r e t u r n flow s h a l l e n t e r t h e r e s e r v o i r below t h e normal o p e r a t i n g l e v e l of t h e f i e l d . A b r e a t h e r h o l e s h a l l b e p r o v i d e d and s h a l l b e p r o t e c t e d by a n a i r cleaner.

6.

VALVES A l l v a l v e s s h a l l have a working p r e s s u r e r a t i n g a t l e a s t e q u a l t o t h e maximum o p e r a t i n g p r e s s u r e s o f t h e system. The c o n t r o l v a l v e s h a l l b e a 4-way r o t a r y s e l e c t o r v a l v e of t h e d i s c t y p e , equipped f o r o i l s e r v i c e . The s e a l s s h a l l l i m i t i n t e r n a l leakage t o 1 drop p e r minute a t t h e r a t e d p r e s s u r e . E x t e r n a l l e a k a g e s h a l l b e z e r o . The c e n t e r s h a l l b e open o r c l o s e d a s s p e c i f i e d o r shown on t h e d r a w i n g s . R e l i e f v a l v e s s h a l l b e a d j u s t a b l e w i t h i n t h e r a n g e of 50% t o 100% o f maximum r a t e d p r e s s u r e . The a d j u s t m e n t s h a l l be s e c u r e d by a locknut o r p r o t e c t i v e cover. Bypass v a l v e s , when i n c l u d e d i n a t r a v e l l i m i t c i r c u i t , s h a l l h a v e c a p a c i t y e q u a l t o t h e pumping r a t e o f t h e s y s t e m f o r normal operation.

HYDRAULIC LINES A l l h y d r a u l i c l i n e s s h a l l h a v e working p r e s s u r e r a t i n g s a t L e a s t e q u a l t o t h e maximum o p e r a t i n g p r e s s u r e of t h e s y s t e m w i t h a s a f e t y f a c t o r (based on b u r s t i n g s t r e n g t h ) o f 4 . Hydraulic l i n e s t h a t w i l l be l o c a t e d under water o r i n a c c e s s i b l e f o r regular inspection s h a l l be s t a i n l e s s s t e e l tubing o r pressure h o s e of s y n t h e t i c r u b b e r o r p l a s t i c w i t h w i r e o r s y n t h e t i c f i b e r reinforcing. F i t t i n g s f o r e i t h e r tubing o r hose s h a l l be s t a i n l e s s s t e e l . Hose f i t t i n g s s h a l l b e p e r m a n e n t l y a t t a c h e d by f a c t o r y methods. F i t t i n g s s h a l l a l l o w n o l e a k a g e and s h a l l n o t unduly r e s t r i c t flow i n t h e passages they connect. For t h a t p a r t of t h e p i p i n g p r o t e c t e d from t h e w e a t h e r and a c c e s s i b l e f o r r e g u l a r i n s p e c t i o n s e a m l e s s c a r b o n s t e e l t u b i n g c a n be used. F i t t i n g s s h a l l have c o r r o s i o n p r o t e c t i o n of cadmium p l a t i n g I f d i s s i m i l a r m e t a l s must be j o i n e d , p r o t e c t i o n a g a i n s t o r equal. g a l v a n i c c o r r o s i o n s h a l l be p r o v i d e d . M e t a l l i c h o s e c o u p l i n g s t h a t w i l l b e dragged i n t o p l a c e i n a c o n d u i t s h a l l h a v e a wrapping of c o a l - t a r t a p e of t h i c k n e s s s u f f i c i e n t t o provide a water proof cover a f t e r i n s t a l l a t i o n .

HYDRAULIC FLUID Hydraulic fluid shall be supplied in accordance with the manufacturer's recommendations for the equipment supplied and the operating conditions stated under Construction Details. INSTALLATION INSTRUCTIONS The manufacturer shall submit complete installation data including instructions for adjustment for all components supplied for this systern. PAINTING Each item of equipment shall have paint protection for all metal except stainless steel or electroplated metallic surfaces. The cylinder and other components that will be submerged shall have protection against such exposure. In the absence of a paint option certified by the manufacturer for such conditions, these items will be painted by System I under Specification 22, Cleaning and Painting Metalwork. Other components, housed in the control station, shall have paint coatings equal to Paint System D or E under Specification 22.

B.

Installing Hydraulically Operated Slide Gates

SAMPLE CONSTRUCTION SPECIFICATION 210.

INSTALLING- -HYDRAULICALLY OPERATED SLIDE GATES -

The work shall consist of furnishing and installing hydraulically operated slide gates, complete with all controls and other necessary appurtenances.

2.

MATERIALS The gates and controls furnished shall conform to the requirements of Material Specifications 128, 134 and 300. All gates shall be furnished complete with hydraulic hoisting equipment and other necessary appurtenances.

3.

INSTALLING GATES The Contractor shall install the gates in a manner that will prevent leakage around the seats or binding of the gates during operation. Surfaces of metal against which concrete will be placed shall be unpainted and free from oil, grease, loose mill scale, surface rust and other debris or objectionable coatings. Anchor bolts, thimbles and spigot frames shall be secured in true position in the forms and held in alignment during the placement of concrete. Concrete surfaces against which rubber seals will bear or against which flat frames or plates are to be installed shall be finished to provide a smooth and uniform contact surface. When flat frames are installed against concrete, a layer,of bedding mortar shall be placed between the frame and the concrete.

4.

INSTALLING HYDRAULIC ASSEMBLY The hydraulic cylinder, pump, valves, connecting lines and fittings shall be installed in accordance with the manufacturer's recommendations and as shown on the drawings, unless otherwise approved by the Engineer. The cylinder shall be mounted as shown on the drawings. Alignment shall be established so that neither gate nor cylinder will bind during any phase of operation.

5.

OPERATIONAL TESTS After the gate and hydraulic lift assembly have been installed, they shall be cleaned, lubricated and otherwise serviced by the Constractor in accordance with the manufacturer's instructions. The gate will be required to maintain a set position for twentyfour (24) hours with a maximum permissible movement due to internal leakage of 0.25 inches. The Contractor shall test the gate and hydraulic lift assembly by operating the system several times :throughout its full range of operation. He shall make any changes and adjustments that are necessary to insure satisfactory operation of the gate system subject to approval of the Contracting Officer.

6.

MEASUREMENT AND PAYMENT The work will not be measured. Payment for the hydraulically operated slide gate assembly will be made at the contract lump sum price. Such payment will constitute full compensation for all labor, materials, equipment and all other items necessary and incidental to the completion of the work including furnishing and installing anchor bolts, housing and all specified appurtenances and fittings.

7.

TYPICAL CONSTRUCTION DETAILS AND ITEMS OF WORK Class of gate - 00-00 (seating - unseating head) Type of frame (flat, spigot, flange, etc.) Type and size of opening (square, round, etc.) Type of wedge (cast iron, bronze, etc.) Type of seating surfaces (cast iron, bronze, etc.) Special gate requirement (self contained, nonrising stem, flush bottom opening, etc.) Type, capacity of hydraulic control system The stem block shall be shaped so as to turn in the gate recess for threading to the pis ton rod. The maximum operating pressure for this system (opening) will be psi. The operating pressure for closing will be

psi.

The range of temperature for operation of this system will be 0 from F to + OF. 1I The cylinder shall have bore, I' stroke mounting style. Piston rod extensions, wrench flat and port locations shall be included as detalled on the drawings.

The pump s h a l l have a pressure c a p a b i l i t y of psi. flow s h a l l be i n t h e r a n g e (gpm, cu i n l m i n ) t o (gpm, cu i n l m i n )

Volume of

.

The r e s e r v o i r s h a l l have a minimum c a p a c i t y of

cubic inches.

The c o n t r o l v a l v e s h a l l have a (n) ( c l o s e d o r open) c e n t e r and p o r t s with s t r a i g h t threads. s h a l l be s i z e

The r e l i e f v a l v e s s h a l l be a d j u s t a b l e w i t h i n t h e range of psi to (-9

-3

-3

p s i . T h e i n i t i a l s e t t i n g ( s ) s h a l l be r e s p e c t i v e l y ) a s d e t a i l e d on t h e drawings.

psi

NOTE & Reduction of stem diameter may be mode if stoinless steel stems are used

I

Stem Diometer tn mches

I

-

<

J

- A bronze lift nut is recommended i f the lift selection [sneor the upper limit of the part~culorhondwheel size zone ond less than 40)pull is required

For verhcol gate lift ignore mformation per?,amingto ' L i f t Pedestal Sire". Structure Size"

GATE OPENING (add 3" to height and width) 012 sq. feet

I

I

I

I

0.3

0.4

0.5

0.6

I

I

l

l

0.7 0.8 0.9 1.0

1

I

1.5

2

I 3

I

I

I 4

I

I

5

I

I

l

l

6

7

8

l l 910

I

I

15

I

20

25

SELECTION CHART

EXAMPLE PROBLEM G

m

I. Outlet Conduit Diameter

21 "

2. Maximum Water Depth to Centerline of Gate

20 '

Handwheel or Geared

I 2

of Fmbankment

---

PROCEDURE Enter Maximum Water Depth(2o1) Enter Gate D m (21")+5' = 24"

Maximum Water Surface --------------

Head to Gate

.

Lift Pedestol Size Gate Stem Diameter L l f t Handwheel Diameter or Gear Ratio Stem Pedestal Spacing ( s a. Encased Stem b Unencased Stem

Use of hydraulic controls should be invest~goted

Stem Pedestal Outlet Conduit

I

1

nfet Structure

Outfef Structure

FIGURE D-I GATE CO~TROLSELECTION CHART EWPU Portland, Oregon

CONSTR. COST /#CLUES: /. Stem ond threading

2. Splices l o t 20.0) 3. Golv. pipe

5. End bushings 6. Adjustab/e stem guide Z R/C stem pedestals

Unencased Stem - Pedestal Spacing ( f e e t )

Note: Enter this chart with the unencosed stem pedesto/ spac/ng and stem diameter required to sutisfy fhe head-gate s k e relation shown in figure D - I .

FIGURE D-2

GATE STEM ENCASEMENT SELECTION CHART EWP Unit Portland, Oregon

ENCASED

SQ HEAD MACH. BOLTS

Iz

HEAVY WALL ENCASING SIZE OF VOL. OIL 2.SEAMLESS RIVETS PIPE DIA. PACKING QTS./FT. STEEL TUBING I" 3 I" 15' 3" 1 ~ 0 . D . 1.D.x 7" 2- 5 x 2" Countersunk IT 16 0.184 5" 3" 3" " 3" I j j 0 . D . l~ 1.D.x 8" 2- 4 " x 2 j j 2" 0.488 8 3" " 7" 5" 1" 5" IgO.D. 1jgI.D.x 9 " 2 - ?1 " x 2 V 0.743 8 ?

2 - 2I" x 27I"

approximofe/y

I

2 ~ 0 . ~ .9"I ~ l . D . x2 9- ~~ ' " x3"

0.627

2-- 5" x 2 T 3"

1.031

2-4

P/oce weafher sea/ abo ve r/;orupped section c/ear of confro/ strucfure

STEM ,

UNENCASED STEM

STEM

I

-7

'I

8 1

Ig

"

1"

2

*

#I

2

$'

I" 2

3"

3"

2 - 8 X 1 4 3" I" 2-Zx 24

8

3"

I"

X

34

Not e : F i / / wifh SAE 20 motor o i / ,

0

ga~ons

S f o h less st e e / stem

I

Should be constant diameter f o r f u l l l e n g t h although m a t e r i a l changes f r o m stainless to carbon steel. T W O -thirds o f the sleeve splic? s h a l l project beyond the upper stem.

" Braided waterproof

DETAIL WEATHER SEAL Steel washer, drill

S e e / washer

OPTIONAL WEATHER SEAL

OPTIONAL OIL FILLER STEM SPLICE

GATE STEM SPLICE

F I G U R E D- 3

GATE STEM DETAILS E W P Unit Portland, Oregon

Note.'

Fi// with SA E 20 motor oi/, opproximale/y (7 ga//ons

u

R a c e weother sea/ above ripropped section b/&7f of control structure.

Note .' Place oil sea/ between g a t e frome and headwa//. See Figure 0 - 3 for splice fable

Seomless sfeel tubing

Carbon steel stem Std. golv coupling Braided waterproof flax or f e / t pocking Z~

gg

DETAIL OIL SEAL

DETAIL STEM SPLICE

l-0 m

5

m

GATE STEM SPLICE

DETAIL WEATHER SEAL

@ PLAN

PLAN

SIDE ELEVATION

SIDE ELEVATION

UNENCASED

ENCASED

Note: -

L ocofion and spocing o f onchof bolts vary wifh type o f sf em guide used See Fig. D-6, D - 7 , D - 8 . Concrefe volume = 0./05 cu.yds.

GATE STEM PEDESTAL 5

0

I

FEET

IN

SCALE

SECTIONAL ELEVATION

STEEL SCHEDULE Location

Mark S i z e Quan. L e n g t h

Type

A

T o ta I Length

B

GATE STEM PEDESTAL P 4 0 / .. P402

4 4

-

p p

P403

4

3 2 2

3'-off jr/ 0 '-2" 0'- 8 of9'-0" 2'- 3 " sir -4'-6 2'-9" Str 5' -6" ' I

f

f

If

Use when consfruction drawings ore to be reduced one ha/f size

knTM YY

S T E E L SCHEDULE

.1

a S:ze aDL n G ~ T ES T E M P E D E S T A L

str

W B T/

BAR TYPES FIGURE 0-5 Use when ~ 0 n s fuction f drab ,7qs ore to be reproduced fu// s l i e

GATE STEM PEDESTAL EWP Unit Portland, Oregon

0"

Dia. gate stem Dio. vent pipe D i a . g a l e stem

0'' channel

PLAN

SIDE V I E W

Adjusting I I

I II

1

x":/

pipe stub

1

See Figure C - 6 f o r vent diameter

ELEVATION

* S t d . galv. pipe

Note.' For unencased stem use /2" pipe stub, the same,digmeter as encasing pipe, through U bo/t c/omp.

GATE STEM GUIDE FIGURE D-6 Not to Scale

ADJUSTABLE STEM GUIDE AND VENT PIPE HANGER EWP U n ~ tPortlond, Oregon

I,

D i o . vent p i p e

(3"

Honger bolts

Gote stem

PLAN

SIDE VIEW STEM DIA.

-R7

0

1

.

x

E N C A S M ' T CHANNEL HANGER@ H A N G E R PIPE* DIA. SlZE(7"long) STRAP SIZE BOLTS

I'

1

1 'I

z

111

111

6 " x 3"- 1 6 . 3 ~I I x a x 2"

3" a x

8"

Otlx011

Hanger strops straps

*

S t d go/v. pipe

@ Hanger bo/f size and spacing requires /urger straps than sfock fittings provide

ELEVATION

GATE STEM GUIDE Scale in F e e t

FIGURE 0-7

ADJUSTABLE STEM GUIDE AND VENT P I P E HANGER EWP Unit P o r t l a n d , O r e g o n

PLAN

SIDE V I E W

Note:

Refer to gate supplier's catalog for size selection

L

I I

I I

1

ELEVATION

GATE STEM GUIDE Not to Scale

FIGURE 0 - 8

ADJUSTABLE STEM GUIDE AND VENT PIPE HANGER E WP Unit Portland, Oregon

F -

ELEVATION

PLAN

' " U"u. -BASE P L A T E

~ I L C

CAPACITY C O N C R E T E

@

2 0 0" 800* 2,200'

@ @

6,000*

1

STEEL

0 . 2 7 cu. yds. 0.47cu.yds. ,0.74cu.yds. 44.25' 2.41cu.yds. 18.05*

..,.A THRU , .i-20544 DETAIL FIG. E Fig. No. D - I0 Fig. No. D - Il

D- 17 1

D-17

Fig.No. D - 1 2 Fig.No. 0-13

1 0 , 0 0 0 ~ 3.70cu.yds. 2 4 . 0 5 ~ F i g N o . D - 1 4

D-18

--

D-I9

D- 19

nut

r bolt,

SECTIONAL ELEVATION

Vent pipe

PLAN

GATE LIFT PEDESTAL I

Note: -

0 IN

FEET

For /ift se1ect;on and handwhee/ s ~ z e refer to F ~ g u r eD -1. For handwheel bracket detai/ see f i g u r e D - / 7 Specify bronze or cost iron /ift nut Inlet of vt??ntpl;ot? to consist of 0 screened (galv. /8mesh) sfreef ell and 90° e l / securely fastened to the lift pedesta/

FIGURE 0-10

GATE LIFT PEDESTAL SIZE A EWP Unit Portland,

oregon

- Diu. hundwhee/ /ift, /ift, -lift nut I'

f "xx 12'' , 12" unchor unchor bolt, bolt, 4 required.

SECTIONAL ELEVATION

Vent pipe

PLAN

GATE LIFT PEDESTAL I

Note:

SCALE

0

5 IN

FEET

For lift selection and handwheel size r e f e r t o f i g u r e D -/. f o r /tmdwhee/ bracket detai/ see Figure D- 17 Specify bronze o r cost iron / i f f nut hlet of vent pipe to consist of 0 screened fgulv. lBrnesh) street ell and 90 e l l secure/y fastened to lift pedes t o /

FIGURE D - l l

GATE LIFT PEDESTAL SIZE 8 EWP Unit Portland, Oregon 7 - L - 20544- 8

SECTIONAL ELEVATION

SECTION

@

SUPPORT ANGLE DETAIL

$! &&

0 ,'b

BOTTOM FACE

Sfr

PLAN

BAR TYPES

GATE LlFT PEDESTAL SCALE

IN

FEET

For lift selection and handwhee/ s/ze refer to Figure D - / Specify bronze or cost iron /ift nuf Refer fo figure D- 6 for "U "bolf size Refer to Figure D - /5 or Figure D - l6 for sfeel schedule Venf p/pe no f shown. lnlet o f vent pipe fo consisf of a screened fgolv /8meshl streef e l l and 90° e l l securely fosfened fo the /iff pedesfa/

FIGURE D - 12

GATE LlFT PEDESTAL SIZE C EWP Unit Portland, Oregon

/

Enclosed gearpedesfo/ / i f f

anchor boNs in manufacturer 's

Note: If pedestal is placed in two sections, a shear key will be provided bet ween each section .

SECTIONAL ELEVATION

Vent pipe not shown place as required.

Weather

PLAN

GATE LIFT PEDESTAL I

SCALE

0 IN

SUPPORT ANGLE DE TAI L

.,?A 1' B S PA

BAR TYPE

Note :

Refer to Figure D - 6 for l ' ~ " b o l t For gem ratio see Figure D - l Refer t o Figure 0 - /5 or D - /6 f o r stee/ schedule Vent pipe not shown. lnlet of vent pipe to consist of a screened lgo/v. /8mesh) street e l l and 90° e l l securely fastened to the lift pedesfol

FIGURE D - 13

GATE LlFT PEDESTAL SIZE D EWP Unit Portland, Oregon

7 - L- 2 0 5 4 4 - D

Note:

/f pedestd is p/aced i n two sections, o shear key will be provided between each section. Vent pipe not shown, p/ace as required.

CBlONAL ELEVATION

7

.to"

-

SUPPORT ANGLE DETAIL

-

LIFT PEDESTAL I

Note: -

5

0

0 IN

Refer to Figure D - 6 for 'h1I b o l t size For gear rotlo see Figure D -/ Refer t o f i g u r e D - /5or D - /6 for stee/ schedule Vent pipe not shown. /n/enf of plpe t o consist of a' screened fqalv. /$mesh) street e / / and 90 O eN secure4 fastened to the lift pedestal

-FEET

SPA

B A R TYPE FIGURE D - 1 4

GATE L I F T PEDESTAL SIZE E EWP Unit Portland, Oregon

Verify bolt locofions from Mfr's. shop drawings

,-

j i x 2" slot

slot

SECTION

w

ELEVATION

@

PLAN I2

* Handwheel diometer -inches

SCALE

IN

INCHES

HANDWHEEL BRACKET FIGURE D- 15

HANDWHEEL BRACKET FOR GATE LIFT PEDESTAL SIZE A 8 6 EWP Unit Portland, Oregon

.Verify bo It /ocations from Mfr 5. shop drawings

PLAN

2-

f M r

/zl/

anchor bolts

ELEVATION

BASE PLATE 6

SCALE

0 IN

I N CH ES

FIGURE D- 16

BASE PLATE FOR PEDESTAL SIZE C FOR LIFTSS HB 30 EWP Unit Portland, Oregon

ond countersink underside 7"

7"

8 x 2g d o t

I

PLAN

IT

from Mfr's. shop drowinqs.

head shall be countersunk ond s/otted.

4 -f

'lx

/2

88

..

anchor bo/ts

.

..

f i r Pedestd D, /ift with qeor ratio 4.'/,use F p / o t e . For Pedestal E, lift yith use / p/ate. gear ratio /2.'/,

2''bolt,

4

.-

countersunk heod SCALE

COUNTERSINK DETAIL

BASE PLATE

IN

INCHES

FIGURE 0-17

BASE PLATE FOR GATE LIFT PEDESTALS SIZE D S E EWP Unit Portland, Oregon

STEEL Locat~on

SCHEDULE

Mark Size Quan. L e n g t h

7

Tot a l Length

0

A

Type

GATE LlFT PEDESTAL

GATE L I F T PEDESTAL SlZE C

STEEL SCHEDULE Location

Mark Size Quan. Length

A

Type

Total Length

B

,

1

1

GATE LlFT PEDESTAL 10401

1

4

1

4

1

6'9"

1

SPA

I 2'-3" 1

/

1'-6"

I

1

3L011~ 7 ~ 0

GATE LlFT PEDESTAL SlZE D

I

I

S T E E L SCHEDULE Location

Mark Size Quan. L e n g t h Type

0

A

Total Length

GATE LlFT PEDESTAL I~4011 4

1

4

1

9'-01'

I

1

SPA 2'4"

1

3'-1''

1

3'-6"

1 3610"

GATE LlFT PEDESTAL SIZE E

Note:

Use w i t h Std. Drwg. 7- L - 2054 4 C, D, o r E when construction drawings are to be reduced one h a l f size.

FIGURE D - 1 8

GATE LlFT PEDESTAL STEEL SCHEDULE EWP Unit Portland, Oregon

I

I

1

STEEL SCHEDULE

1

Location Mark

I I

I

I 1A 1

Size Quan. Length Type

GATE

B

L l F T PEDESTAL S I Z E C

S T E E L SCHEDULE Location Mark r

1 GATE

t

Size Quan. Length Type . A

8

I

Tota l lLength

L I F T PEDESTAL

1

[ ~ 4 0 1 4

1

4

1 6'- 9 " ISPA 12'-3" 1 1'-6" 1 3 ' - 0 " 1 2 7 ' - o W

GATE L l F T PEDESTAL

I Location Mark

Size Quan. Length Type

A

I

SIZE 0

STEEL SCHEDULE

L

:

Total ICILength]

B

I

I c

otal lLngth

GATE L l F T PEDESTAL [ ~ 4 0 1 4[

1

4

1 9 ' - 0 " [ S P A 12'-5"13'-1"

13'-6"136'-0"

GATE L l F T PEDESTAL S I Z E E Note : -

Use with Sfd. Drug. 7- L -20544

C, D or E when construction drowings a r e to be reproduced ful/ s i z e .

FIGURE D-19

GATE LIFT PEDESTAL STEEL SCHEDULE EWP Unit Portland, Oregon

0-5; Typical Control S t a t i o n Minimum equipment i n c l u d e s : Riser I n s t a l l a t i o n 1. 2. 3.

Hydraulic c o n t r o l s a r e shown f o r i r r i g a t i o n o u t l e t and second-stage f l o o d c o n t r o l p o r t s . C y l i n d e r s a r e shown mounted on g a t e frame o r w a l l b r a c k e t . Hydraulic c o n t r o l l i n e s a r e grouped i n s i n g l e p r o t e c t i v e c o n d u i t . No a c c e s s catwalk i s n e c e s s a r y .

Pump Reservoir 4-way C o n t r o l Valve

J u n c t i o n box houses connections. The c o n t r o l s a r e shown mounted on a standard pipe s e c t i o n . Protect i o n can be p r o v i d e d by a l o c k i n g manhole cover and frame. A l t e r n a t e mounts may v a r y from a simple p o s t t o a walk-in shed.

Options i n c l u d e powered pumps and s o l e n o i d v a l v e s f o r remote e l e c t r i c control.

C o n t r o l s can be l o c a t e d a t t h e c r e s t of t h e embankment o r a t a downs t ream measuring d e v i c e ,

Trash racks and c y l i n d e r guard a r e o m i t t e d t o show c y l i n d e r d e t a i l s .

Hydraulic Tubing Tubing i s s t a i n l e s s s t e e l o r high p r e s s u r e rubber hose e n c l o s e d i n p r o t e c t i v e conduit of r i g i d plast i c o r galvanized s t e e l pipe. Tubing and c o n d u i t can be conformed t o berms o r o t h e r i r r e g u lar forms and i s n o t d i s t u r b e d by o r d i n a r y s e t t l e m e n t . The p r o t e c t i v e c o n d u i t can a l s o be used t o s a t i s f y t h e v e n t i n g requirements. Typical I r r i g a t i o n I n l e t Hydraulic c y l i n d e r i s a J.I.C. Stand a r d w i t h s t a i n l e s s s t e e l p i s t o n rod. S i d e l u g mount i s shown b o l t e d d i r e c t l y t o concrete surface.

FIGURE D- 2 0

HYDRAULIC CONTROL APPLICATI ONS EWP Unit Portland, Oregon

1 Go t e d i a + 3" (inches)) [ ~ r e incl. a gate seat (ft!)

NOT l.

2. 3. 4.

(cylinder area minus r o d urea/. 5. Chart 3- Sfd. indicates standard rod, O.S. indicates oversize' rod. 6. Chart 3 is zoned for severs/ cylinder bore and piston r o d sizes. Colored area t'n each zone has an operating pressure between 2000 - 3000 p s i ; t h e rest of the zone less than 2000 psi.

E x a m p l e Problem GWEN: 5.06 sq ft !. Outlet gate diam. (or area)(24 3)* 2 . Maximum head of water to f of gate 20 f f 3. Weight o f gat? s /ide fCata/og data) ZOO /bs 4. Stroke = ( 2 4 t 4 7 = 28 in 5. "L" dimension measured as shown above 36 in Chort 3 for front flange mount

1-

+

Distance -L (inches) Stroke - S ( i n c h e s )

PROCEDURE.' Enter Chart / with gate size plus seat a//owance and head. From intersection proceed down 45O guide /ine t o to the Gate Slide Weighf, Chart 2, theg fiorizontally to intersection with vertical line from L va/ue i n Chart 3. Enter Chart 4 with stroke and cylinder selection for reservoir capacity.

/. force /For design o f bracket and anchorage)

2 . Cy Iinder Bore Size 3. Pressure 4. Piston Rod 5 . Reservoir Capacity

4700 / b s 2in < 3 0 0 0 psi 0.s. 45 cu in

F L O W DIAGRAM FIGURE D-21

S E L E C T I O N C H A R T FOR HYDRAULIC CYLINDERS EWP Unit Portland, Oregon

Wiper,

P0rts7 /Air

bleeds

/

Vee type piston packing

Steel heads

,

Seamless steel tubing

1 I11

SECTION THROUGH T Y P I C A L CYLINDER LTegsesure

4-way rotary selector valve

Reservoir

gate slide.

For use in the Cylinder

Optional circuit for power installation to

Set design opening pressure

HYDRAULIC PIPING DIAGRAM (PREFERRED)

HYDRAULIC PIPING DIAGRAM (ALTERNATE)

I----'

CONTROL STATION

F I G U R E D- 2 2

T Y P I C A L D E T A I L S FOR HYDRAULIC C Y L I N D E R GATE C O N T R O L S E W P Unit Portland, Oregon

MOUNTING STYLE Side FOOTMount

CARTER

HANNlFlN

CNS lNon Cushioned) CFS ICurhioncd Front End) CRS ICurhioned Rear Endl

MILLER

H72

C-HlO -

--

H73

H52

H53 H50 D Prefix

INTERCHANGEABLE STANDARD ROD ENDS

REFERENCE -

Male (Standard) Male (Alternate)

--

Male (Optional)

Style #3

Fernale

Style # 4

CARTER CONTROL, INC.

--

--

-

-Style 12

Style 3

FIGURE 0-23

HYDRAULIC CYLINDER INTERCHANGE CHART E WP Unit P o r t l a n d , Oregon

Gote Opening

(spf t ) 1 I I I I 1

(odd 3" to height and width 1

I 1 0.5.6.7.8.91.0 1.5 2

1

1 1 1 , 1 , 1 1 1 1 1 3

4

5 6 7 8 9 I0

I

I

J

15 20 25

F O R C E IN MECHANICAL LIFT

r

Force (Ibs) I

-

EVALUATION O F POWER REQUIREMENT

FIGURE D - 2 4

CONTROL OPERATION MANUAL vs POWER EWP Unit Portlond,Oregon

SECTION E

- CONDUIT

Contents

Page

INTRODUCTION 11. 111.

.. .....,. ...,....... CONDUIT TYPES ....... .... .... ...... A. Precast Concretepipe. . . . . . . . . . . . . . . . B. Flexible Conduits ................. C. Monolithic Conduits . . . . . . . . . . . . . . . . . GENERAL CRITERIA

Figures Types of Precast Concrete Pipe

............. ......... .............

Monolithic R/C Conduit with Steel Liner R/C Monolithic Conduit Detail R/C Monolithic Conduit Detail Monolithic Outlet Conduit Joint Details Outlet Conduit Composite Construction Outlet Conduit Details (ES-154)

Conduit Anti-Seep Collar Selection Chart

.

Corrugated Metal Diaphragm Anti-Seep Collar Settlement Curve and Simple Camber Conduit Camber on Parabolic Curve

9

9

E-1 E-2 E-2

E-2 E-3

E-ii Tables

.Standard

Page

.....

E-1

Wall Thickness

E-2

Camber Data

E-3

Recommended

E-4

Recommended Corrugated or Spiral Aluminum Pipe Gages

R/C and Cylinder Pipe

....................... Corrugated Steel Pipe Gages . . . . . . . . . ,

.

E-29 E-30 E-31 E-31

SECTION E

I.

-

CONDUIT

INTRODUCTION One of the more critical elements in the safety of a dam is the conduit that carries water through the embankment. Not only must the conduit be watertight against internal water pressures, it must be designed to carry exterior vertical and transverse loads to resist structural failure. It must be set on a grade that takes into account the magnitude of foundation settlement and the variation of this settlement along its length. It must allow for .readjustment of the individual pipe lengths without failure of the joints. These joints must allow for "stretch" in the conduit as a result of foundation displacement. And lastly, the backfill must be carefully placed along the conduit so that seepage water will not find a more favorable path along the contact surface than that it must face through the embankment itself. These conditions are met in part by the selection of the proper conduit type and strength, whether it be a rigid pipe in a concrete cradls a flexible pipe, or a monolithic box, set on a grade considering camber requirements. Adding anti-seep collars insures the path along the contact zone will be a longer seepage line than that through the embankment. O £ course all of these precautions mean little if the installation does not conform to the requirements of the construction specifications.

11.

GENERAL CRITERIA Because the conduit is such a vital part in the safety of the dam, criteria is very explicit and limiting in those cases where loss of life could result from embankment failure. To ensure that these limiting criteria are not overlooked, the following tabulation of existing engineering memoranda is included and these must be complied with as each restriction applies: 1.

Engineering Memorandum SCS-27 (Rev.) Earth Dams.

2.

Engineering Memorandum SCS-42 (Rev.) R/C Pipe Drop Inlet Barrels.

3.

Engineering Memorandum SCS-58, and Fittings.

Corrugated Aluminum Pipe

In addition to the memoranda, procedures for analysis are continued in the following :

1. NEH, Section 6, Structural Design 2.

Technical Release No. 5, The Structural Design of Underground Conduits

3,

Technical Release No. 18, Joint Gap Computations for R/C Pipe Drop Inlet Barrels

Appropriate specifications include: Spec. Spec. Spec. Spec. Spec. Spec. Spec. Spec. 111.

No. No. No. No. No. No. No. No.

41, R/C P r e s s u r e P i p e 51, Corrugated Metal Pipe Conduits 52, S t e e l P i p e C o n d u i t s 541, R/C P r e s s u r e P i p e 542, C o n c r e t e C u l v e r t P i p e 551, Zinc-Coated I r o n o r S t e e l C o r r u g a t e d P i p e 552, Aluminum C o r r u g a t e d P i p e 553, S t e e l P i p e and F i t t i n g s

CONDUIT TYPES A.

P r e c a s t Concrete P i p e Four t y p e s o f p r e c a s t p i p e a r e recommended a s s u i t a b l e f o r u s e a s a c o n d u i t t h r o u g h a n embankment. 1. 2. 3.

4.

ASTM AWWA AWWA AWWA

361, 300, 301, 302,

R/C R/C R/C R/C

Low Head P r e s s u r e P i p e S t e e l C y l i n d e r Type Non-Prestressed S t e e l C y l i n d e r Type P r e s t r e s s e d Non-Cylinder Type Non-Prestressed

The p r o c e d u r e s p r e s e n t e d i n T e c h n i c a l R e l e a s e No. 5 s h o u l d b e used i n d e t e r m i n i n g s t r u c t u r a l r e q u i r e m e n t s o f t h e p i p e .

G e n e r a l d e t a i l s o f p r e c a s t p i p e a r e shown on F i g u r e E-1. The i n s i d e d i a m e t e r l i s t e d on t h i s f i g u r e f o r t h e d i f f e r e n t types i n a l l inclusive. I n c r e m e n t a l s i z e s and some t y p e s a r e n o t a v a i l a b l e from a l l p l a n t s . ~ r e i ~ chots t s c a n add cons i d e r a b l y t o c o n s t r u c t i o n c o s t s f o r a p a r t i c u l a r job and s h o u l d b e a c o n s i d e r a t i o n i n comparing a l t e r n a t e d e t a i l s . I n a d d i t i o n t o t h e p r e c a s t p i p e l i s t e d above, a c o n c r e t e c y l i n d e r p i p e complying w i t h F e d e r a l S p e c i f i c a t i o n SS-P-381 h a s been used i n c o m p o s i t e c o n s t r u c t i o n as a l i n e r i n a job-placed r e i n f o r c e d c o n c r e t e c o n d u i t . C o n d u i t w a l l r h k c k n e s s e s h a v e b e e n l i s t e d i n T a b l e E-1 f o r ready reference a s required. B

.

F l e x i b l e Conduits Of t h e f l e x i b l e c o n d u i t s , a c o r r u g a t e d m e t a l i s t h e most C o r r u g a t i o n s may b e a n n u l a r o r s p i r a l and commonly used. t h e c o n d u i t made o f g a l v a n i z e d i r o n o r aluminum. Use o f c o r r u g a t e d p i p e is l i m i t e d t o f i l l h e i g h t s o f 25'-0" o r less.

Aluminum pipe shall not exceed 36" diameter and internal pressures shall be limited to 15 feet of head. Aluminum material shall not be used where the pH is less than 4 or greater than 9. Where the product of the storage in acre feet times the height of the d d is less than 3000 and meets the conditions above, the following tables apply: Recommended corrugated metal pipe gages for various pipe diameters and fill heights are given in 1.

Table E-3 for corrugated steel.

2.

Table E-4 for corrugated aluminum.

Special precawtions should be taken in the backfill operation. Because of its light weight, the pipe will be displaced upward when backfilling in the lower third. To avoid this displacement there is a tendency by the construction crew to under-compact this material. This results in a poor contact zone between the soil and conduit with a potential for piping and eventual embankment failure. To insure adequate compaction, .the canduit should be preloaded with sandbags to resist the uplift until the lower 1200 of the conduit is backfilled. As an alternate the pipe can be bedded in concrete. Welded steel pipe may be used as a liner for a monolithic conduit of small diameter. As such it no longer is classed as a flexible pipe.

C. Monolithic Conduits Poured in place conduits are used in many installations for both the small diameter as well as the larger box conduit. In the small diameter conduit a welded steel pipe is used as a liner which serves as an interior form. The joints of this pipe are "stab" type with a rubber ring. A trench is excavated to neat lines and serves as the bottom and side exterior forms for the conduit walls. On a non-compressible foundation no joints are provided in the concrete. For a compressible foundation a joint similar to the detail shown on Figure E-3 or E-5 is used.

1/ Defined as the difference in elevation in feet between the emergency spillway crest and the lowest point in the original profile on the centerline of the dam.

Conduit w a l l t h i c k n e s s v a r i e s w i t h t h e s o i l type i n t h e f o u n d a t i o n and embankment a s w e l l a s t h e h e i g h t of f i l l over t h e c o n d u i t . F i g u r e E-2 was developed t o s i z e t h e c o n d u i t w a l l t h i c k n e s s and r e i n f o r c e m e n t f o r t r i a l s e c t i o n s . Succ e s s i v e c h o i c e s between two t y p e s of c o n d u i t embedment cond i t i o n s , t h r e e t y p e s of f o u n d a t i o n s , and f i n a l l y t h r e e t y p e s of embankment s o i l s narrows down t h e problem t o t h e t r i a l s e c t i o n . An e x t e n s i o n of t h e f i n a l zone t o an i n t e r s e c t i o n w i t h t h e h e i g h t of e a r t h cover w i l l i n d i c a t e t h e governing s t r u c t u r a l c o n d i t i o n . From t h i s p o i n t a v e r t i c a l p r o j e c t i o n t o t h e W l i n e upward i n t h e s h e a r zone, downward i n t h e moment zone, and then a h o r i z o n t a l p r o j e c t i o n t o c o n d u i t d i a m e t e r w i l l provide t h i c k n e s s and t r a n s v e r s e reinforcement r e q u i r e ments. L o n g i t u d i n a l r e i n f o r c e m e n t i s a r b i t r a r y b u t should c o n s i s t of a t l e a s t e i g h t # 5 b a r s f o r c o n d u i t d i a m e t e r s o v e r 12 i n c h e s . L a t e r a l s p a c i n g of l o n g i t u d i n a l b a r s should n o t exceed 12 i n c h e s . IV.

JOINTS The i n t e g r i t y o f t h e e n t i r e i n s t a l l a t i o n depends t o a g r e a t e x t e n t on j o i n t d e t a i l . For c o n c r e t e c o n d u i t s any r o t a t i o n due t o s e t t l e ment and e l o n g a t i o n of t h e c o n d u i t must t a k e p l a c e a t t h e j o i n t s . Procedure f o r c a l c u l a t i n g j o i n t e x t e n s i b i l i t y i s given i n T e c h n i c a l Release No. 18. Recommended j o i n t d e t a i l f o r r i g i d c i r c u l a r c o n d u i t s c o n s i s t s of an r r 0 II r i n g rubber g a s k e t s e a t e d i n a groove i n a s t e e l s p i g o t r i n g t o b e i n s e r t e d i n a s t e e l t e l l , A s e c t i o n a l d e t a i l of t h i s The r e s t of t h e j o i n t j o i n t assembly i s shown on F i g u r e E-1. d e t a i l s shown on t h i s f i g u r e a r e n o t a c c e p t a b l e i n c o n d u i t s through embankments. S p i g o t r i n g c r o s s s e c t i o n w i l l v a r y w i t h manufacturer conduit diameter and j o i n t e x t e n s i o n requirement. I n w e s t e r n a r e a s Carnegie shape M 3818 and M 3516 a r e commonly used. The a n n u l a r s p a c e between t h e a d j a c e n t p i p e ends should b e f i l l e d w i t h a m a s t i c j o i n t s e a l e r f o r j o i n t f l e x i b i l i t y i n s t e a d of t h e cement g r o u t normally recommended by t h e manufacturer. The b e l l and s p i g o t j o i n t i s used f o r b o t h t h e p r e c a s t p i p e a s w e l l as t h e composite c o n s t r u c t i o n (shown i n Figure E-6). For m o n o l i t h i c c o n c r e t e c o n d u i t s with a r e c t a n g u l a r opening t h e j o i n t d e t a i l w i l l vary with conduit s i z e . Several d e t a i l s a r e shown on Figures E-3 and E-5. The Carnegie shape j o i n t mentioned above i s recommended f o r welded s t e e l pipe. An a l t e r n a t e j o i n t would be a D r e s s e r coupling. L e a s t d e s i r a b l e i s a welded j o i n t .

For c o r r u g a t e d metal c o n d u i t s t h e w a t e r t i g h t c o u p l i n g band i s used.

V.

ANTI-SEEP COLLARS To insure that any seepage along the contact surface between the conduit and embankment will be less than that through the soil itself, anti-seep collars are used. These are projections from the conduit that effectively increase the length of the seepage path. Anti-seep collars must be structurally independent of the conduit. To insure this, roofing felt and preformed joint filler is used in the contact surfaces between the conduit and collar. If the collars are placed too close together, the seepage path would tend to bridge the space between the collars since this is the path of least resistance. Although keeping the seepage from the conduit-soil contact surface, close spacing would require an excessive number of collars. Anti-seep collar spacing should be restricted to a minimum of 10'-0 and a maximum of 25'-0. The length of the projection and the number of anti-seep collars varies with agency requirements. Normally a 2'-0 vertical projection is recommended and a number of collars equivalent to a 15% increase in conduit length. Various soil types and zoned embankments add to the design problem. To simplify the proportioning of anti-seep collars, Figure E-8 was developed. On it, embankment types and soil types are considered in selecting either a 15% (1.T5) or a 20% (1.20) increase in seepage length. In zoned fills the vertical projection should be increased so that close spacing can be avoided and still retain the collars in the impervious zone where they will do the most good.

VI. CAMBER IN CONDUITS Foundation settlement can be expected under the combined.weightof an embankment and the water impounded in the reservoir. The magnitude of settlement is a function of the applied load; depth, relative density, moisture content and permeability of compressible foundation materials; and time. Generally clays, silty, clays and medium and high plastic silts are the most compressible materials. Settlement characteristics of these materials must be determined by consolidation tests on undisturbed samples. The magnitude of settlement is computed using procedures of Standard Drawing 7-N-15474 (not included here) and is part of embankment design. Camber is designed for a conduit so that as settlement occurs, the invert of a cambered conduit theoretically approaches uniform slope. Camber for a conduit can be defined as a curve which approximates the inverse of the settlement curve. If a conduit is not cambered a sag will develop as settlement occurs, the conduit joints will spread at the bottom, the conduit can leak and cause serious damage to the structure.

Camber i s designed f o r a c o n d u i t i n a d d i t i o n t o computing t h e j o i n t e x t e n s i b i l i t y requirements i n accordance w i t h T e c h n i c a l Release 18. S e t t l e m e n t does n o t o c c u r a s a g r a d u a l advancement of a smooth curve. Although t h e f i n a l s e t t l e m e n t curve i s approximately a uniform c u r v e , enough i r r e g u l a r i t y w i l l e x i s t i n t h e conduit p r o f i l e t o r e q u i r e adequate j o i n t e x t e n s i b i l i t y . The s i m p l e s t method o f computing camber i s t o u s e two l e n g t h s of uniform s l o p e a s shown i n Figure E-10. T h i s method i s used only f o r s h o r t c o n d u i t s w i t h s m a l l s e t t l e m e n t . The j o i n t a t t h e grade change i s t h e only one designed n o t t o s p r e a d as s e t t l e m e n t o c c u r s .

A p r e f e r r e d method i s t o d e s i g n a curve approximating t h e i n v e r s e of t h e s e t t l e m e n t curve. T h e o r e t i c a l l y , a l l j o i n t s on such a c u r v e a r e designed n o t t o s p r e a d a s s e t t l e m e n t o c c u r s , A procedure f o r t h i s method i s given below. Because of t h e many v a r i a b l e s a f f e c t i n g t h e magnitude of s e t t l e ment, i t i s unwise t o i n n o c e n t l y assume t h a t a l l f o u n d a t i o n s can b e t r e a t e d a l i k e . However, f o r s m a l l dams l e s s than 30 f e e t high on s h a l l o w f o u n d a t i o n s , t h e magnitude of s e t t l e m e n t i s s m a l l , p r e c i s e computations f o r camber a r e seldom j u s t i f i e d and t h e followi n g g e n e r a l assumptions can b e made, 1.

Shallow f o u n d a t i o n i s d e f i n e d as depth t o noncompressible m a t e r i a l l e s s t h a n one-half t h e h e i g h t of dam.

2.

Depth of compressible f o u n d a t i o n i s uniform under t h e dam.

3.

S e t t l e m e n t curve i s a p a r a b o l i c curve w i t h maximum s e t t l e m e n t n e a r t h e c e n t e r l i n e of t h e dam.

4.

Maximum s e t t l e m e n t can be e s t i m a t e d t o b e 4 p e r c e n t t o 5 p e r c e n t of foundation depth when n o t o t h e r w i s e computed.

I n t h e following procedure c e r t a i n items a r e f i x e d by s i t e condit i o n s and t h e embankment d e s i g n . These i n c l u d e :

1.

L

-

T o t a l l e n g t h of c o n d u i t .

2.

Y

-

T o t a l drop between i n l e t and o u t l e t of c o n d u i t .

3,

A

-

Magnitude of s e t t l e m e n t , assumed t o b e l a r g e s t a t embankment c e n t e r l i n e .

4.

6

-

Camber h e i g h t a t p o i n t X.

5.

R

-

Length of s t a n d a r d p i p e o r c o n d u i t s e c t i o n s t o be used. ( 9 is a p a r t i a l length.)

A j o i n t should b e p l a c e d a s n e a r a s p o s s i b l e t o t h e c e n t e r l i n e of t h e dam. Negative s l o p e i n t h e cambered c o n d u i t should b e avoided. Use zero s l o p e through t h o s e r e a c h e s where camber d e s i g n i n d i c a t e s negative slope i s necessary.

F i g u r e E-ll i s a d i m e n s i o n l e s s p l o t o f s e t t l e m e n t vs. c o n d u i t l e n g t h f o r a p a r a b o l i c s e t t l e m e n t curve. T a b l e E-2 c o n t a i n s d a t a f o r computing maximum d e f l e c t i o n a n g l e a t a j o i n t f o r various l e n g t h s of standard reinforced concrete pipe. Procedure f o r T a b u l a r Computations 1.

Determine number o f p i p e l e n g t h s r e q u i r e d (n number)

2.

Determine

3.

Determine L1

.

-

+? = L

1 "W 2

= l o w e s t whole

nG

+ Z(E1.

t o p o f Dam

-

El. I n l e t ) .

T h i s should b e a m u l t i p l e of R s o t h a t a p i p e j o i n t f a l l s n e a r c e n t e r l i n e o f dam. 4.

DetermineL

5.

Determine average uniform s l o p e and t a b u l a t e e l e v a t i o n o f a v e r a g e grade l i n e a t each p i p e j o i n t (Col. 7 ) .

6.

Compute camber: Refer t o page E-9

L-L1

=

2

a.

Tabulate R

b.

Tabulate C R

c.

Tabulate

1

and R

1

(Col. 2 ) .

and C R 2 (Col. 3)

C R 1 and -

1

d.

2

and 1 0 f o r t a b u l a t i o n form,

CR 1 ( ~ o l . 4)

2 6 ( ~ o l .5) -

From F i g u r e E-11 r e a d

A 6 a ( c o ~ . 6)

e,

Compute camber = 6 =

f.

T a b u l a t e a v e r a g e g r a d e e l e v a t i o n - e l e v a t i o n of i n v e r t a t upstream end l e s s drop p e r l e n g t h of p i p e (Col. 7).

g.

Compute camber g r a d e e l e v a t i o n = average grade e l e v a t i o n p l u s camber (Col. 6 + Col. 7) = (Col. 8).

A

VII.

EXAMPLE

Given:

The e a r t h dam d a t a used i n t h e example problem o f S e c t i o n B , and c h o i c e s o f 20 in.. s t e e l p i p e , 2 1 i n . R/C p i p e , o r 24 i n . CMP. Top of dam E / /25.0

1

Center of gate

E l I02 2

Determine:

A

=

0.4 f t ( d e t e r m i n e d b y s o i l s e n g i n e e r )

R

=

16 f t ( u s e s t a n d a r d pipe)

1.

Camber f o r t h e o u t l e t c o n d u i t by computing joint elevations.

2.

The number and s p a c i n g of c o l l a r s , comparison o f c o n d u i t t y p e s and q u a n t i t i e s f o r 20 i n . s t e e l p i p e , 2 1 i n . R / C p i p e and 24 i n . CMP.

Problem A n a l y s i s :

1.

Find camber:

a. b.

c. d. e. f.

Determine c o n d u i t l e n g t h . Determine t h e number o f f u l l p i p e l e n g t h s . Determine Ll and L2. Determine t h e a v e r a g e u n i f o r m s l o p e . Determine d r o p p e r p i p e l e n g t h . T a b u l a t e R1 and R 2 .

g.

T a b u l a t e C R 1 and C R 2 ( n o t e 2 h o r i z o n t a l s c a l e s on F i g u r e E-6)

h.

Tabulate

CR2 -

CR1 -

L2

1

Determine

j.

Determine 6 Determine a v e r a g e g r a d e e l e v a t i o n . Determine camber g r a d e e l e v a t i o n .

k. 1. 2.

6 from F i g u r e E-11. -

i.

A

Details: a. b.

c. d.

Determine the number o f c o l l a r s , F i g u r e E-8. Determine encasement and c o l l a r s f o r 20 i n . s t e e l p i p e . Find combination of 2 1 i n . R / c p i p e , c r a d l e and c o l l a r meeting s t r e n g t h requirement. Check minimum gage and diaphragm s i z e f o r 24 i n . CMP.

Solution :

U s e L1 = 80 f t

=

5 pipe lengths

Number of f u l l p i p e l e n g t h s L2

=

131

-

80

=

51' = 3

-

Drop p e r l e n g t h o f p i p e :

=

-121.

No.

I;?

8

Dl = 16(0.010) = 0.16

6

Joint

=

16 16' lengths = 1 - 3' length

Average Grade Elevation

Camber Grade Elevation

t

1 Joint No.

I

2

3

R2

X2 or

EL2 -

x k2

L2

4 1

5

6

7

6 -

6

Average Grade Elevation

A

8

Camber Grade Elevation

100.71 100.43 100.08 100.00

2.

Details

a.

Determine t h e number o f c u t o f f s and s p a c i n g : The dam i s a homogeneous embankment t y p e ( 1 ) w i t h CL m a t e r i a l . R e f e r r i n g t o F i g u r e E-8 shows t h a t t h e 1.15 c h a r t i s recommended. E n t e r t h e 1 . 1 5 c h a r t w i t h L' = 111 f t and r e a d V = 2.5 f t f o r n = 4 , V = 2.0 f t f o r n = 5 , and V = 1 . 5 f t f o r n = 6. S i n c e V a 2.0 f t Is recommended as a n a t i o n a l s t a n d a r d , u s e n = 5. The spacing is then determined by S = L' o r S = 111 = n 4- 1 18.5 f t , u s e S = 18.5 f t . 6

b.

Check 20" R / C m o n o l i t h i c c o n d u i t . Using a p r o j e c t i n g c o n d u i t c o n d i t i o n w i t h a f o u n d a t i o n o f h i g h l i q u i d l i m i t c l a y , a n embankment m a t e r i a l w i l l b e assumed t o b e of low p l a s t i c i t y . With a h e i g h t o f e a r t h c o v e r of 25 f t and a p i p e d i a m e t e r o f 20 i n . , e n t e r F i g u r e E-2 as shown by example. Find t = 6 i n . (minimum t h i c k n e s s ) and s t e e l = #5 @ 1 2 i n . Q u a n t i t i e s from T a b l e J-El show t h i s c o n d u i t t o , r e q u i r e (131) (0.19) = 24.9 cu yd o f c o n c r e t e and (131) (11.04) = 1446 l b o f s t e e l .

+

Using D 2 t = 2'-8'' and V = 2.0 f t from T a b l e J-E2, f i n d t h e a n t i - s e e p c o l l a r s r e q u i r e ( 5 ) ( 0 . 8 4 7 ) = 4.2 c u yd o f c o n c r e t e and ( 5 ) ( 4 7 . 2 ) = 236 l b o f s t e e l .

c.

Check 21" R / C c o n d u i t , T a b l e J-E4 l i s t s 21" R / C p i p e a s b e i n g a v a i l a b l e m e e t i n g t h e AWWA C-302 ( f c = 6000 p i ) , ASTM C-361. Using t h e p r o c e d u r e s a s p r e s e n t e d i n T e c h n i c a l R e l e a s e 5 f i n d t h e c o m b i n a t i o n of p i p e and c r a d l e t h a t s a t i s f i e s t h e s t r e n g t h requirements.

d.

Check f o r 24" CMP. I f c o r r u g a t e d m e t a l p i p e i s a c c e p t a b l e , minimum p i p e gages a r e l i s t e d i n T a b l e s E-3 and E-4. For a f i l l h e i g h t o f 25 f t , f i n d r e q u i r e d p i p e gage o f 1 6 f o r c o r r u g a t e d s t e e l and 1 2 gage f o r aluminum. For e i t h e r s t e e l o r aluminum, t h e s t a n d a r d manufactured a n t i - s e e p c o l l a r i s 72" x 72" o f 1 4 gage m a t e r i a l . D e t a i l s f o r b o t h c o l l a r and c o u p l i n g band are shown on F i g u r e E-9.

CONCRETE C Y L I N D E R

REINFORCED CONCRETE

ASTM Designation C361 Diameters 12 thru 168 inch Pressures to 125;feet of head

Federal Specification SS-P-381 Diameters 12 thru 36 inch; Presfires to 25+f Prestressed

AWWA Standord C300 Not prestressed Diameters 2 0 thru 96 inch Pressures 4 0 thru 2 6 0 psi

AWWA Standard ~ 3 0 2

a

AWWA Standard C302 Diameters 12 thru 96 inch Pressures less than 45 psi

z

AWWA Standard C302

a W

3 a

AWWA Standard C301 Prestressed Diameters 12 thru 96 inch Pressure as specified

AWWA Standard C302

ASTM Designation: C 76 Diameters 12 thru 108 inches

JOINT

DETAIL

Note: Alternate Joint Detai/s shown a r e typico/ o f the variation in joint t y p e s that a r e a v a i / o b / e for most classes of pipe. They o r e not a / / acceptable on conduits thru dam embankments. The ring assemb/y detai/ shows a stee/ ring joint for- minimum joint extensibi//ty. ;

+lgOt ring. Carnegie shape Morcquivolent-a-'

SECTIONAL DETAIL

\

6

I

s=

4

' - g ~ u b b e rgasket.,

Z

m

-S

I

RING ASSEMBLY

k:

i

.,re

FIGURE E - I

TYPES OF PRECAST CONCRETE PIPE EW P Unit Portland, Oregon

F I G U R E E-2

MONOLITHIC R / C CONDUIT WITH STEEL LINER E W P Unit Portland, Oregon

wotersfop

ALTERNATE

/Anti-

21

seep collar

"

Pf filler

Steel //her with sfob jointsandwoferseal

n -

6" double bulb

Steel plate

W

II--8

SECTIONAL ELEVATION

ANTI - SEEP COLLAR

Note: Max. joint spac~hg= 32.0' Refer to Figure E - 2 for fhichness f and r e i n f o r c i n g - reouirernenfs

I

E N D VIEW FIGURE E - 3

R/C M O N O L I T H I C CONDUIT DETAIL E W P Unit Portland, Oregon

Note.' Use 8 /ongitudino/ burs when 0

>/2" Str

SPC

SECTION

@

BAR TYPES Not t o

Scale

-

p p

STEEL SCHEDULE Location

Mark Size Quan. Length Type -

A

Total Length

B L

CONDUIT ENCASEMENT C C

o/

02 C 03

SPC

. ,-

2

-

Str

Use when construction drawings ore to be reduced one h d f size

CONDUIT ENCASEMENT C 01

1

SPC

C

02

T2

C

03

Str

Use when consfruction drawings ore to be reproduced fu// size

-

FIGURE E - 4

R/C MONOLITHIC CONDUIT DETAIL EWP Unit Portland, Oregon

Alternote I Preformed joint fi//er

H

.

:.:.:.: (3 .: ' .'

a A>.:;

.

.'

...... ':.

'

..

,. :.

E/ecfro ver t water stop

.

..., , ;

..

+

*-

.

i ,

Pin we/ded to cover ~ / a l e . + -

Bottom Member

Asphdt coated steel p/ate (Cost in p/acej

f

" x 2" str;p of pre f m d /oint filler (Cast in place)

8"threaded stud -Steel p/ate

Side and Top Member

Alternate 2

11

J " rubber water stop

f 2 bo/ts

used to deve/op compression in the wafer stop)

Alternate 3 Copper water stop

2;'' to 3'.

FIGURE E- 5

MONOLITHIC OUTLET CONDUIT JOINT DETAILS E W P Unit Portland, Oregon

FRONT ELEVATION

SECTI O M L ELEVATION

w

NOT TO SCALE

OUTLET CONDUIT AND ANTI - SEEP COLLAR

FIGURE E - 6

OUTLET CONDUIT COMPOSITE CONSTRUCTION E WP Unit Portland, Oregon

JOINTS S E A L E D WITH RUBBER GASKET I N POSITIVE GROOVE

L

- -,I-

-1

\

PlPE JOINT

APPROVED JOINT SEALER

T--

DISPLACEMENT CHARACTERISTICS

SECTION TYPICAL ARTICULATION JOINT

2

BLOCKS, OPTIONAL

L-& P R E F O R M E D JOINT

JOINT ROTATlON CAPACITY

WHEN A1 CRADLE USED: CUT LONGITUDINAL BARS AT 3'' FROM EACH SIDE OF ARTICULATION JOINT. USE NO DOWELS.

PRIOR APPROVAL OF PlPE AND PlPE JOINT DETAIL PROPOSED FOR USE, TO BE REQUIRED BY THE SPEC,IFICATIONS.

CLASS (a) DAMS MORE THAN 50 FT. HIGH, AND A L L CLASS (b) AND CLASS (c) DAMS

' 1

PREFORMEDJOINT FILLER, 18'' WIDE -----j

SECOND POUR, POUR WlTH CRADLE

ALTERNATE FOR CLASSIa)DAMS LESS THAN 5 0 FT. HIGH PREFORMEDJOINT FILLER, 12" WIDE

$"DIA BUT NOT L E S S THAN 6" *4@12

HORlZ

#4@12

VERT

€1

F-

\

OF L BOTTOM CRADLE

-BOTTOM OF CRADLE

C

A c

'J

FINISH COLLAR SURFACE TRUE AND SMOOTH

1

4

ONE LAYER OF HEAVY, SNIOOTH SURFACE, ASPHALT TREATED,

SECTION 8 - B

9

-I

C

SECTION C- C

SECTION E-E

SIDES OF ANTI-SEEP COLLARS TO BE FORMED ABOVE BOTTOM OF CRADLE MAX SPACING OF COLLARS=25'

5 5 L B S PER SQUARE.

DETAIL SHOWN FOR EARTH FOUNDATION FOR ROCK FOUNDATION, FOUND BOTTOM OF CRADLE ON ROCK

SECTION F- F (SHOWING STEEL)

(SHOWING STEEL)

ROOFING FELT APPROX WT

AND SMOOTH

ROOFING FELT APPROX WT 5 5 LBS PER SQUARE MAX. SPACING OF COLLARS = 2 5 :

DETAIL SHOWN FOR EARTH FOUNDATION. FOR ROCK FOUNDATION, FOUND BOTTOM OF CRADLE ON ROCK LINE AND KEY COLLAR 6"lNTO ROCK

LINE AND KEY COLLAR 6 " INTO ROCK

DETAIL OF A N T I - S E E P

A l . CRADLE

RADIANS

FILLER

DETAIL O F PlPE CONDUIT SECTION ON k - A 2 CRADLE SHOWN

I',

CAPACITY INCHES

A 2 CRADLE

D E T A I L OF A N T I - S E E P

GOLLAR

61 BEDDING

PlPE AND CRADLE OR BEDDING ALTERNATES M I N I M U M T H R E E EDGE B E A R I N G T E S T STRENGTH L O A D

A1 CRADLE

A2 CRADLE

GOLLAR

El BEDDING

SCOPE: I. Pipe Diometers: ~ = 2 4 ' 30, : 36, 4 2 , ond 4 8 CRITERIA: I. Materlols (except ptpe):

Concrete: Class 8,f c ' = 4 0 0 0 psi, f c = 1 6 0 0 psi Re~nforcingSteel: l n t e r m e d ~ a t egrade 2. Applicable Criterio: Engineering Memorondum SCS-27 Engmeering Memorandum SCS-42 (rev.2) Technlcal Release No. 5 Technlcal Releose No. 18

REFERENCE: ES 154

FIGURE E - 7

OUTLET CONDUIT DETAILS EWP Unit Portland, Oregon

Minumum Number (n) of Anti-Seep Collar Required

.

I

Minimum

Number ( n ) of Anti-Seep Collars Required

HOMOGENEOUS EMBANKMENT

ZONED EMBANKMENT

Core material in zoned embankm'ent I

0

EMBANKMENT TYPES

0

4

I

EMBANKMENT SOIL USE CHART CLASSlFlATlON TYPE

3,4, 5,6 ML, SM

1.20 1.20

:

F I G U R E E- 8

CONDUIT ANTI- SEEP COLLAR SELECTION CHART EWP Unit Portland, Oregon

Notes:

I. A l l materials t o be i n accordance with applicable S. C . S . construction material specifications.

I

.'Install diaphragm with ' corrugations vertical

:I

6. A l l corrugated metal pipe diaphragms shall beaspholt coated after shop fabrication hos been performed.

:I

*I 2 3 Space 8"c -

2. Unassembled diaphragms shall be marked by painting or tagging t o identify matching pairs. 3. The lap between the two half sections and between the pipe and connecting band shall be caulked with asphalt mastic a t time of installation. 4. Welding may be substituted f o r rivets in fastening 2I1x 2"x 3 ~L s1to p~pe.Welds must be on each side o f angles and on each corrugation ridge in contact with angle. 5. D =outside diameter of W.S.Pipe or nominal diameter of C.M.Pipe.

$X

for

2" slotted holes bolts

U" dia.

Space 8"c-c

I

~

I

~,Provide ~ ~ 4 holes ~ ~ f 0.r '/211 X 4 V2l1 carriage bolts

.

=

~

FABRICATION TABLE FOR C. M. DIAPHRAGM

I

I

I

DIA.

I

.it

* 3i

Dl APHRAM SIZE

DIMENSIONS W(W1DTH) H(HEIGHT

I

both sides

nk lugs for conn -

Corrugated metal sheet welded t o center of band.

E L E V A T I O N OF U N A S S E M B L E D D I A P H R A G M ( No scale 1

SECTION B - B

*Minimum gage for"Livestock Water Tanks and other dams not over 10 feet high. * * ~ i n i m u m gage for all other dams - 12'' dio. smallest size allowed.

FIGURE

E-9

CORRUGATED METAL DIAPHRAGM ANTI-SEEP COLLAR

FIGURE E- I 0

SETTLEMENT CURVE AND SIMPLE CAMBER E W P Unit Portland, Oregon

TABLE E-1

WALL THICKNESS STANDARD R/C AND CYLINDER PIPE

Conduit C-300 Inside Iiameter inches 12

AWWA C-301 Embedded Cylinder

C-302 C-3Q2 fk = 6000 f: = 4500 psi psi Wall Thickness t i n c h e s (minimum)

C-301 Lined Cylinder

ASTM C-361 '6-76

TABLE E-2 CAMBER DATA

I

I. D.

-

In.

Approx. deflection p e r j o i n t (a)

Sin a

M i n i m u m radius of curve 32 f t . lengths

I

12

3O 05'

.0541

Remarks I

594 '

Maximum j o i n t gap = O.D. x s i n a

TABLE E-3 RECOMMENDED CORRUGATED STEEL PIPE GAGES

I

Conduit Diameter

I

Fill Heigbt

-

feet

TABLE E-4 RECOMMENDED CORRUGATED OR SPIRAL ALUMINUM PIPE GAGES

Conduit Diameter inches

Fill Height

-

feet

SECTION F

.OUTLET

STRUCTURES Page

~orlt ents

. I1. I

I11. IV

.

. VI . V

. VIII . VII

...................... CANTILEVER OUTLET . . . . . . . . . . . . . . . . . . . PWD BASIN . . . . . . . . . . . . . . . . . . . . . . . ..................... IMPACT BASIN SAF BASIN . . . . . . . . . . . . . . . . . . . . . . . OTHER OUTLETS . . . . . . . . . . . . . . . . . . . . . OUTLET SELECTION CHART . . . . . . . . . . . . . . . . . INTRODUCTION

F-1 F-1 F-2 F-3 F-4 F-6 F-6

EXAMPLE

. B. A

Problem1 Problem 2

..................... .....................

F-7 F-7

Figures

F-4

................. Impact Basin Outlet Structure . . . . . . . . . . . . . Riprap Size Selection Curves . . . . . . . . . . . . . . Cantilever Outlet Plunge Pool . . . . . . . . . . . . .

F-5

Cantilever Bent Selection Chart

F-1 F-2 F-3

F-6 F-7 F-8 F-9 F-10 F-11

PWD Outlet Structure

............

............ Cantilever Outlet Bent (ES-106) . . . . . . . . . . . . Cantilever Outlet Detail (ES-107) . . . . . . . . . . . Cantilever Outlet Timber Bent . . . . . . . . . . . . . Construction Drawing .PWD Basin . . . . . . . . . . . . Outlet Structure Selection Chart . . . . . . . . . . . . Cantilever Outlet Bent (ES-105)

F-21 F-23 F-25 F-27 F-29 F-31 F-33

F-35 F-37 F-39 F-41

SECTION F

I.

-

OUTLET STRUCTURE

INTRODUCTION Flow from t h e r e s e r v o i r through t h e o u t l e t c o n d u i t may b e c a r r i e d f o r some d i s t a n c e through an i r r i g a t i o n p i p e l i n e d i s t r i b u t i o n system o r d i s c h a r g e d just beyond t h e t o e o f t h e embankment. I n any e v e n t , w a t e r w i l l emerge a t r e l a t i v e l y h i g h v e l o c i t y whether d i s c h a r g i n g submerged i n a p o o l o r f r e e l y i n t o t h e a i r . Where i t i s t o b e c a r r i e d i n an e a r t h channel, an o u t l e t s t r u c t u r e i s r e q u i r e d t o d i s s i p a t e o r absorb e x c e s s energy. The flow s h o u l d p a s s i n t o t h e e a r t h channel a t none r o s i v e v e l o c i t i e s f o r a l l s t a g e s of d i s c h a r g e t o p r e v e n t undermining of t h e o u t l e t . S e v e r a l t y p e s of o u t l e t s t r u c t u r e s have been used s u c c e s s f u l l y i n S e r v i c e work. C o n d i t i o n s under which each of f o u r t y p e s s h o u l d b e used h a s been d e s c r i b e d i n terms of h y d r a u l i c l i m i t a t i o n s and economics on F i g u r e F-11. The s t r u c t u r e most s u b j e c t t o v a r i a t i o n i n c o s t due t o s i t e c o n d i t i o n s i s t h e c a n t i l e v e r o u t l e t and i t s plunge p o o l . T h i s i s e s p e c i a l l y t r u e i f t h e p o o l r e q u i r e s armor p l a t i n g . The o t h e r t y p e s compared a r e t h e PWD, Impact, and t h e SAF b a s i n s .

11.

CANTILEVER OUTLET

The c a n t i l e v e r o u t l e t i s a low c o s t t e r m i n a l s t r u c t u r e t h a t depends Its economy on t u r b u l e n c e i n a plunge b a s i n f o r energy d i s s i p a t i o n . i s most a p p a r e n t i n s i t u a t i o n s where t h e s o i l m a t e r i a l i n t h e downstream channel is e r o s i o n r e s i s t a n t . I t s economy i s a l s o e v i d e n t when r o c k i s r e a d i l y a v a i l a b l e and cheap and used a s a n armor p l a t i n g of t h e plunge b a s i n where t h e f o u n d a t i o n m a t e r i a l i s less e r o s i o n r e s i s t a n t . Whether armor p l a t i n g w i t h rock o r n o t , a preformed s c o u r h o l e i s recommended. I f n o t preformed, t h e m a t e r i a l s c o u r e d from t h e plunge b a s i n w i l l b e d e p o s i t e d i n t h e channel downs t r e a m forming an a r t i f i c i a l b a r r i e r r a i s i n g t h e t a i l w a t e r l e v e l and p o s s i b l y submerging t h e o u t l e t t o a f f e c t t h e h y d r a u l i c s of t h e c o n d u i t system. I t i s i m p o r t a n t t h a t t h e j e t t r a j e c t o r y have some drop from t h e c o n d u i t t o pool w a t e r s u r f a c e f o r b e t t e r energy d i s s i p a t i o n w i t h i n t h e pool.

A s c h e m a t i c diagram and nomenclature o f t h e c a n t i l e v e r o u t l e t and t h e s t i l l i n g b a s i n i s g i v e n on F i g u r e F-4. Design c r i t e r i a f o r p r o p o r t i o n i n g t h e b a s i n i s given i n SCS Design Note No. 6 , The v a l u e o f p i n F i g u r e F-4 s h o u l d b e a minimum of one f o o t . For c a l c u l a t i n g q u a n t i t i e s above t h e p l a n e of t h e downstream c h a n n e l i n v e r t , t h e f o l l o w i n g e q u a t i o n i s given a s supplementary t o t h o s e of Design Note No. 6:

The nomenclature i s t h a t given on F i g u r e F-4 except t h a t y i s t h e v e r t i c a l d i s t a n c e t o t h e upper l e v e l p l a n e o f e x c a v a t i o n o r r i p r a p . The a r e a of t h e downstream channel e n t r a n c e i s i n c l u d e d i n t h e volume and must b e deducted from t h e r o c k q u a n t i t i e s . I n f o r m a t i o n on s t r u c t u r a l d e t a i l s f o r t h e c a n t i l e v e r o u t l e t i s given i n F i g u r e F-5 through F-9. I n a l l c a s e s t h e bottom of t h e c a n t i l e v e r b e n t should e x t e n d t o a l e v e l below t h a t of t h e b a s i n bottom, u n l e s s i t r e s t s on rock.

Use of t h e c a n t i l e v e r o u t l e t should b e r e s t r i c t e d t o s i t e s where i t i s compatible w i t h t h e s u r r o u n d i n g improvements and p i p i n g i s n o t a f o u n d a t i o n problem. On o c c a s i o n a submerged o u t l e t h a s been used; t h e s e should be l i m i t e d i n use t o s m a l l o u t l e t s and low system heads. No d e s i g n c r i t e r i a i s given h e r e f o r t h e p r o p o r t i o n i n g of t h i s o u t l e t type. PWD BASIN PWD i s an a b b r e v i a t i o n f o r P u b l i c Works Department. This basin i s recommended f o r low head systems. A diagram of t h i s s t r u c t u r e and i t s p r o p o r t i o n s f o r v a r i o u s head-conduit d i a m e t e r combinations i s given i n F i g u r e F-1. For e f f e c t i v e o p e r a t i o n , t h i s s t r u c t u r e

depends on t h e f o r m a t i o n o f a h y d r a u l i c jump f o r energy d i s s i p a t i o n , consequently t a i l w a t e r i s an i m p o r t a n t c o n s i d e r a t i o n . P l a t e F-1 i l l u s t r a t e s f a u l t y o p e r a t i o n as a r e s u l t of i n a d e q u a t e t a i l w a t e r . The c r e s t of t h e o u t l e t s i l l should b e set a t t h e same e l e v a t i o n a s t h e i n v e r t of t h e c o n d u i t o u t l e t . Flow v e l o c i t i e s i n t h e downstream c h a n n e l should b e i n t h e s u b c r i t i c a l v e l o c i t y range w i t h normal d e p t h e q u a l o r g r e a t e r t h a n c r i t i c a l d e p t h a t t h e s t r u c t u r e s i l l . Riprapping t h e bottom and s i d e s o f t h e channel f o r a d i s t a n c e of f o u r c o n d u i t d i a m e t e r s downstream of t h e s t r u c t u r e i s recommended f o r s h a l l o w t a i l w a t e r c o n d i t i o n s . T h i s w i l l a l s o p r o v i d e t r a n s i t i o n p r o t e c t i o n when t h e channel i s wider t h a n t h e s t r u c t u r e . R e f e r t o F i g u r e F-3 f o r rock r i p r a p s i z e . A sample of a s t a n d a r d drawing f o r t h i s t y p e s t r u c t u r e h a s been i n c l u d e d i n t h i s s e c t i o n a s F i g u r e F-10.

PLATE F-1 IV.

IMPACT BASIN

The impact basin is recommended for use with long duration flows and where the downstream water level will not meet the minimum tailwater requirements for the formation of a hydraulic jump. Entrance velocities should be restricted to less than 30 fps. Figure F-2 is a schematic diagram and a selection chart for various head-conduit size relations within the limits of the hydraulic capacity of this type of structure.

A short length of conduit leading directly into the impact basin should be level or set on a slight positive slope. During low flows, experience has shown the jet leaving a steeper conduit will miss the impact wall completely. Impact basins should not be used with open top inlets where heavy or long debris can be expected unless an extensive trash rack is used.

Riprapping t h e bottom and s i d e s of t h e downstream channel f o r a d i s t a n c e of f o u r c o n d u i t d i a m e t e r s i s recommended. R e f e r t o F i g u r e F-3 f o r r i p r a p s i z e s . For compu~ingt h e h y d r a u l i c s of a f u l l flow c o n d u i t system u s i n g a n impact b a s i n , THE OUTLET WATER SURFACE SHOULD BE ASSUMED TO BE AT THE TOP OF THE BAFFLE WALL. A sample of t h i s s t r u c t u r e has b e e n i n c l u d e d i n t h e completed example i n S e c t i o n H a s F i g u r e H-5. V.

SAF BASIN The S t . Anthony F a l l s h y d r a u l i c l a b o r a t o r y developed an energy d i s s i p a t i n g s t r u c t u r e used e x t e n s i v e l y i n t h e S e r v i c e . T h i s s t r u c t u r e i s known as t h e SAF b a s i n . I t i s recommended f o r long d u r a t i o n flows, h i g h e n t r a n c e v e l o c i t i e s and d i s c h a r g e s i n excess of 400 c f s . This s t r u c t u r e h a s n o t been s t a n d a r d i z e d b e c a u s e of t h e number of v a r i a b l e s involved s o t h a t each i n s t a l l a t i o n i s a s e p a r a t e d e s i g n . NEH 1 4 , ''Chute Spillways", p r o v i d e s p r o c e d u r e s f o r t h e h y d r a u l i c p r o p o r t i o n i n g of t h e SAF b a s i n . The SAF b a s i n depends on t h e h y d r a u l i c jump f o r energy d i s s i p a t i o n . Unless t a i l w a t e r s a t i s f i e s t h e jump requirements over t h e major p o r t i o n of t h e d i s c h a r g e range i n e f f e c t i v e o p e r a t i o n r e s u l t s . The r a t i o , TW/D2, t a i l w a t e r depth (TW) t o depth req u i r e d f o r t h e jump, ( D 2 ) , should b e w i t h i n t h e l i m i t s of 0 . 8 t o 1 . 2 f o r t h e f u l l range of d i s c h a r g e ( s e e P l a t e F-2). However, f o r low d i s c h a r g e s h o r t d u r a t i o n flows t h e t a i l w a t e r r a t i n g curve may exceed t h e TW/D2 r a t i o of 1 . 2 w i t h o u t s e r i o u s consequence. P l a t e F-3 i s an e x c e l l e n t i l l u s t r a t i o n of m a l f u n c t i o n i n a SAF b a s i n because of i n a d e q u a t e t a i l w a t e r . Loss of a h y d r a u l i c c o n t r o l downstream o r d e g r a d a t i o n o f t h e channel i s t h e u s u a l cause of low t a i l w a t e r . Because of low t a i l w a t e r , t h e h i g h v e l o c i t y j e t l e a v e s t h e s t r u c t u r e w i t h l i t t l e energy l o s s f u r t h e r a g g r a v a t i n g t h e downstream s c o u r problem. E l e v a t i o n of t h e SAF apron s h o u l d b e e s t a b l i s h e d by u s i n g t h e l o w e s t roughness c o e f f i c i e n t and a s c o u r e d grade l i n e i n t h e h y d r a u l i c s of t h e downstream channel. E l e v a t i o n of t h e top of t h e SAF s i d e w a l l s h o u l d b e checked u s i n g t h e h i g h e s t roughness c o e f f i c i e n t i n t h e downstream h y d r a u l i c s .

fai/noler rating curve from the jump requirement curve

0

2000 Dischorge

3000

(cfs)

PLATE F-2

PLATE F-3

4000

VI.

OTHER OUTLETS S e v e r a l o t h e r t y p e s and v a r i a t i o n s of t h e above s t r u c t u r e s have b e e n used i n t h e p a s t w i t h s u c c e s s . These h a v e b e e n f o r s p e c i a l installations with limited application. Four d e s e r v i n g s p e c i f i c m e n t i o n a r e t h e M a n i f o l d O u t l e t , B i a n c h i Bench, SCS B a f f l e , and t h e Submerged O u t l e t . No c o v e r a g e o f t h e s e s t r u c t u r e s i s g i v e n here.

VII.

OUTLET STRUCTURE SELECTION CHART F i g u r e F-11 i s n o t i n t e n d e d a s a n a l l i n c l u s i v e e v a l u a t i o n o f o u t l e t s b u t r a t h e r as a n a i d t o t h e l e s s e x p e r i e n c e d i n e l i m i n a t i n g those choices between types of o u t l e t s h y d r a u l i c a l l y i n a d e q u a t e o r e c o n o m i c a l l y u n d e s i r a b l e f o r a g i v e n s e t o f conditions. T h i s f i g u r e h a s b e e n d i v i d e d i n t o two c o n d i t i o n s : Condition 1 - rock r i p r a p is n o t required i n c a n t i l e v e r o u t l e t p l u n g e b a s i n , and Condition 2

-

rock r i p r a p is required i n c a n t i l e v e r o u t l e t plunge basin.

B e f o r e u s i n g F i g u r e F-11, t h e downstream c h a n n e l c o n d i t i o n s should be evaluated. I f rock r i p r a p i s n o t r e q u i r e d , Chart A i n C o n d i t i o n 1 p r o v i d e s a c h o i c e between a c a n t i l e v e r o u t l e t and a PWD b a s i n . The PWD b a s i n s h o u l d b e a c c e p t a b l e o n l y i f t h e t a i l w a t e r r e q u i r e m e n t c a n b e s a t i s f i e d as d e s c r i b e d i n t h e d i s For c o n d u i t d i a m e t e r s c u s s i o n of h y d r a u l i c jump ( s e e P l a t e F-2). t o 30 i n c h e s t h e s t a n d a r d PWD s t r u c t u r e i s more e c o n o m i c a l . Above 30" c o n d u i t d i a m e t e r , f o r low h e a d s , a m o d i f i e d PWD s t a n d a r d s t r u c t u r e i s less e x p e n s i v e t o c o n s t r u c t . It is the d e s i g n e r ' s c h o i c e t o u s e e i t h e r t h e c a n t i l e v e r o r t o modify t h e s t a n d a r d FWD s t r u c t u r e w i t h t h e d i m e n s i o n s shown i n F i g u r e F-1.

I f i t h a s b e e n d e t e r m i n e d t h a t r o c k r i p r a p i s r e q u i r e d downs t r e a m of t h e o u t l e t s t r u c t u r e , C o n d i t i o n 2 a p p l i e s . When t h e u n i t c o s t r a t i o of r e i n f o r c e d c o n c r e t e t o r o c k r i p r a p i s l e s s t h a n 1 3 , s e l e c t a s t r u c t u r e from C h a r t B . A t t h i s p o i n t t h e c h o i c e i s between t h e SAF, Impact and PWD b a s i n s ; t h e d i v i s i o n s between t h e t h r e e t y p e s i s b a s e d on h y d r a u l i c l i m i t a t i o n s . R e f e r e n c e i s made t o F i g u r e F-1 and F-2 f o r f u r t h e r s i z e s e l e c t i o n of t h e PWD o r Impact b a s i n s . However, i f t h e u n i t c o s t r a t i o of r e i n f o r c e d c o n c r e t e t o r o c k r i p r a p i s g r e a t e r t h a n 13, t h e c o s t of a c a n t i l e v e r o u t l e t w i t h armor p l a t e d p l u n g e p o o l s h o h d b e compared w i t h one o f t h e t h r e e s e l e c t e d from C h a r t B.

VIII

.

EXAMPLE By t h e t i m e t h e system a n a l y s i s h a s p r o g r e s s e d t o t h i s p o i n t one of t h e c o n d u i t s would have been s e l e c t e d f o r f i n a l d e s i g n . To i l l u s t r a t e procedure a few comments a r e o f f e r e d r e g a r d i n g t h o s e o u t l e t s s u i t a b l e f o r c o n d u i t s n o t used i n t h e c o n t i n u i n g example.

O r d i n a r i l y m e t a l p i p e ( s t e e l o r CMP) would be c a n t i l e v e r e d from a t i m b e r b e n t . F i g u r e F-11 does n o t r e f l e c t t h e economy i n i n i t i a l c o n s t r u c t i o n f o r t h i s combination of c o n s t r u c t i o n materials

.

Both t h e 20" s t e e l p i p e and t h e 24" CMP would b e c a n t i l e v e r e d from a timber b e n t . D e t a i l s f o r t h e b e n t can b e found on F i g u r e F-9. I f t h e s t e e l p i p e i s t o b e encased a R/C b e n t would b e used and d e t a i l s from F i g u r e s F-6 through F-8 would b e s e l e c t e d . The example w i l l b e c o n t i n u e d u s i n g t h e 21" R / C c o n d u i t . A.

Problem 1 Given:

System head o f 20 f e e t and 21" R / C c o n d u i t .

Determine:

Type o f o u t l e t and c o n s t r u c t i o n drawing d e t a i l s .

Problem A n a l y s i s :

1. E v a l u a t e need f o r armor p l a t e i n plunge p o o l . 2.

Determine o u t l e t t y p e u s i n g F i g u r e F-11.

3.

S e l e c t a p p r o p r i a t e s t r u c t u r e s i z e from F i g u r e F-1, o r F-4.

F-2,

S o l u t i o n : R e f e r r i n g t o F i g u r e F - l l w i t h a head of 20 f e e t and a 21" c o n d u i t s i z e , f i n d c h o i c e s :

B.

1.

I f no armor p l a t i n g i s r e q u i r e d , from Chart A s e l e c t The drawing number can be s t a n d a r d PWD b a s i n s i z e D. found on F i g u r e F-1.

2.

I f armor p l a t i n g i s r e q u i r e d , from Chart B s e l e c t impact b a s i n and r e f e r t o F i g u r e F-2 f o r s i z e and s t a n d a r d drawing number.

Problem 2 Given:

Sys t e m head of 20 f e e t and 21" R / C c o n d u i t .

Determine: C o n s t r u c t i o n c o s t and a n n u a l c o s t of a l t e r n a t e o u t l e t s and e v a l u a t e .

Problem A n a l y s i s :

1.

Calculate construction costs for a. b. c. d.

2. 3.

-

C a n t i l e v e r o u t l e t u n l i n e d plunge p o o l C a n t i l e v e r o u t l e t w i t h armored plunge p o o l PWD b a s i n Impact b a s i n

C a l c u l a t e a n n u a l c o s t s f o r each o u t l e t . Evaluate r e s u l t s .

S o l u t i o n : I n t h i s comparison two a l t e r n a t e s i t u a t i o n s a r e considered :

1.

O u t l e t c o n t r o l w i t h t h e system head t h e same f o r a l l alternates.

2.

O u t l e t e l e v a t i o n (downstream channel g r a d e ) t h e same f o r a l l alternatives.

These a l t e r n a t e c o n d i t i o n s a r e p r e s e n t e d t o i l l u s t r a t e t h e need f o r h a v i n g some i d e a of t h e o u t l e t t y p e d u r i n g t h e i n i t i a l h y d r a u l i c p r o p o r t i o n i n g of t h e system. For t h e c o n s t r u c t i o n c o s t comparisons the f o l l o w i n g u n i t p r i c e s w i l l b e used:

1. E x c a v a t i o n , cu yd Plunge b a s i n and downstream channel Structure 2. 3. 4.

5.

S t r u c t u r e b a c k f i l l , cu yd Rock r i p r a p ( i n c l u d e f i l t e r ) cu yd Reinforced c o n c r e t e , cu yd R/C c o n d u i t , l i n f t

$0.50 1.00 1.00 7.50 100.00 20.00

For t h e a n n u a l c o s t comparison t h e f o l l o w i n g f a c t o r s w i l l b e used:

1. Annual maintenance (% of c o n s t r u c t i o n c o s t ) a. b. c. d.

Concrete s t r u c t u r e E a r t h channel Rock Riprap Earth b a c k f i l l

2.

Project l i f e

3.

I n t e r e s t rate

-

50 y e a r s (no s a l v a g e v a l u e )

-

6% c r f - 6% - 50 = 0.06344

C a l c u l a t i o n s s u p p o r t i n g c o n s t r u c t i o n and annual c o s t s f o r t h r e e d i f f e r e n t o u t l e t t y p e s a r e p r e s e n t e d on t h e followi n g pages F-11 through F-20. From t h e c o s t summaries l i s t e d on page F-20 i t can b e s e e n t h a t c o s t economy f a v o r s t h e PWD o u t l e t f o r a comparable head c o n d i t i o n . For t h e comparable downstream channel e l e v a t i o n t h e c a n t i l e v e r o u t l e t w i t h e a r t h p l u n g e p o o l i s less c o s t l y . Any s i g n i f i c a n t change i n t h e u n i t p r i c e of c o n s t r u c t i o n o r maintenance c o s t s c o u l d change t h e most economical c h o i c e . T h i s s t a t e ment i s e s p e c i a l l y t r u e i f r o c k r i p r a p was r e a d i l y a v a i l a b l e and t h e c o s t of c o n c r e t e was h i g h . The c h o i c e of o u t l e t s t r u c t u r e h a s b e e n reduced t o t h e c a n t i l e v e r o u t l e t and PWD b a s i n . F i n a l s e l e c t i o n w i l l depend on c a r e f u l e v a l u a t i o n of t h e downstream c o n d i t i o n s . From t h e d a t a g i v e n a PWD b a s i n would b e recommended. For purposes o f i l l u s t r a t i o n an impact b a s i n h a s been used i n t h e c o n t i n u i n g example and i n c l u d e d i n S e c t i o n H , Drawing Layout and Summary. The importance of economics i n d e s i g n cannot b e u n d e r r a t e d , b u t t h e d e s i g n e r musr n o t l o s e s i g h t o f t h e p o s s i b i l i t y o f changes i n t h e p h y s i c a l and f u n c t i o n a l r e q u i r e m e n t s of t h e s i t e , and t h e added s a f e t y t h e more c o s t l y s t r u c t u r e might p r o v i d e , such a s : 1.

The impact b a s i n h a s more p o s i t i v e energy d i s s i p a t i o n .

2.

I f o f f s i t e c o n d i t i o n s make t h e t a i l w a t e r r a t i n g c u r v e unrel i a b l e , t h e c a n t i l e v e r b a s i n would be a b e t t e r c h o i c e .

3.

I f t h e o u t l e t d e s i g n c o n d i t i o n i s n o t t h e maximum flow c o n d i t i o n and t h e r e could b e p e r i o d s o f g r e a t e r d i s c h a r g e , t h e FWD b a s i n would b e more s u s c e p t i b l e t o damage.

4.

A e s t h e t i c v a l u e s of one o u t l e t a s compared t o a n o t h e r o u t l e t a r e a c o n s i d e r a t i o n , e s p e c i a l l y i n a more i n t e n s e l y developed area.

COMPUTATION

SHEET

SCS-523 REV 5-58

COMPUTATION SHEET S C S - 5 2 3 REV 5-58

U . S. DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE .-

lJo6 1

SUBJECT

I

NO.

C o s t Estimate

dfrucfure width = 7-'0'' S M DTw g No. f '

I 9 5 8 0-470811

.

.-.- -

.-

I

/mp,~B t ma

F i n

GPO

F/$L/~P f-2

COMPUTATION SHEET SCS-523 REV 5-5B STATE -

--

--

PROJECT

Fur We3f

I

DATE/_

7-b7

G0i.d Out /PI

CHECKED BY

DATE

--

U . S . DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE -. -STATE

.

6Y

.

-

-

-

- .- --

---

--

- -

-

--GPO

Fdr --- ~e5f - -

-

HWE

SUBJECT

.-

PWD 84.512

Cost E stimafe

---

I 9 5 1 0-470067

U p " -

--

COMPUTATION SMEET

SCS-523 REV 5-58

U. S . DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

Pelative Locoiion, of Alfernofe Quflefs

Relative Loco tion o f A l t e r n a t e

OuHet

U. 5. DEPARTMENT OF AGRICULTURE SOlL CONSERVATION SERVICE

--

STATE

HNF

BY SUBJECT

GPO

PROJECT CHECKED B Y

DATE/-7-&7

195s 0-a70867

OU//P/ DATE

JOB NO.

\.

--

A/te//7~fP[dmpdf/sd.

S

H

E

E

T OF

Construction G o s f Summary

Annual Cost Surnrnatv

1

Canti lever

Outlet

I

tmpoet

I

PWD

I

--

EXAMPLE: Select structure size for use with o 24" conduit ond o (oj /o;heod fb) 60 heod Enter chort with proper reservoir sfoqe ond project o i t size. For the /0' heod f i n d size I'D" direct/y. For the 60' heod f i n d size 'F -

~

I"

Outlet conduit

PLAN L" Preformed joint filler I

Pipe dio.

I !

---

I

WS. chon%n

ver t

er thickness

Q-C

~ S

2-4

5-/O /

0' 6"

8-24 /

20-66

58-/32 /20-280250-490450-640

6'

21- 3"

3'- 0''

4'- 0''

5'- 0"

6'-01'

g"

'

1'- 6 '

2)- 0)'

2:6l1

3'-0''

-

-

1 FiNer

loyer thickness = d50 ( 6 "minimumj

Length I

SECTIONAL ELEVATION For riprop size se/ection curves for d50 see Figure F - 3

IStd. Dwg. No. 1

7-E

- 20463

F I G U R E F-I Suffixed

by size l e t t e r

for refinement in quantities f o r vorious conduit types ond sizes,

P.W. D. OUTLET STRUCTURE E W P Unit P o r t l a n d ,Oregon

F-2 3 N o t e : The basin width selected shall be that width directly above or t o the right of

PERSPECTIVE VIEW Example: Conduit dia - - - Velocity - - - - At intersection find- Use standard structure

- - 3 0 inches (fu II pipe flow) - - 2 0 fps - - 10.4 f t basin width size

I I .O feet

SIZE SELECTION CHART The quantities listed are approximate and vary with the size o f the inlet conduit. Revised 6 - 7 0

Reference

:

USDl

~ e p o r t * HYD- 572

FIGURE F - 2

IMPACT BASIN O U T L E T STRUCTURE E WP Unit Portland, Oregon

Equotion anolysis for dS0

Riprap /ffyer thickness Filter layer thickness

L

Ap = Area of the pipe (ff.=l b = bottom widfh ( f t l H = Head (ff.) I$, = Head /ass coefficient for .~ . i ~ e

= 3d', = ds0

FIGURE F-3

RIPRAP SIZE SELECTION CURVES (dS0) EWPUnit Portland, Oregon

Water S u r f a c e a t Maximum Discharge Conduit

--1

Stilling Basin

- Definition

Sketch

thickness of r i p r a p o r t o t a l thickness of r l p r a p and f i l t e r material, f t thickness of riprap, f t t o t d l thickness of r i p r a p and f i l t e r material, ft s i z e of r i p r a p of which 50 percent by weight i s smaller, ft i n s i d e diameter of conduit, ft depth of s t i l l i n g basin below i n v e r t of o u t l e t channel, f% depth of water i n t h e s t i l l i n g basin a t t h e maximum conduit discharge, ft v e r t i c a l d i s t a n c e from t h e i n s i d e crown of t h e conduit t o t h e water surface i n t h e s t i l l i n g basin a t t h e maxin~uhconduit dis&arge, ft mean v e l o c i t y i n the conduit f o r full pipe flow a t maximum discharge, f t / s e c volume between a horizontal plane a t t h e i n v e r t of t h e o u t l e t channel and a surface a t a thickness = a below t h e exposed r i p r a p surface, cu yds volume of r i p r a p below a h o r i z o n t a l plane a t t h e i n v e r t of t h e o u t l e t channel exclusive of t h e volume i n t h e Riprap F i l t e r Cap, cu yds Va=a, - Va=o volume of f i l t e r material,below a horizontal plane a t t h e i n v e r t of t h e o u t l e t channel n t h e Riprap F i l t e r Cap, cu yds including t h e volume : - va=a, = a volume i n t h e Riprap F i l t e r Cap'below a h o r i z o n t a l plane a t t h e i n v e r t of t h e o u t l e t channel, cu yds h o r i z o n t a l d i s t a n c e from t h e o p t l e t end of t h e conduit t o t h e c e n t e r of t h e s t i l l i n g basin, ft For determining t h e depth of t h e s t i l l i n g basin,

For determining t h e position o f t h e s t i l l i n g basin, assuming t h e conduit i s horizontal a t t h e o u t l e t ,

For determining t h e volumes i n t h e s t i l l i n g basin,

V,

=

25(1.167h

+ 1.o6aIs - 0.029(h +

REFERENCE S C S Design Note No. 6

0.36aI3

FIGURE F - 4

CANTILEVER OUTLET PLUNGE POOL E W P Unit Portland, O r e g o n

Note: For conduit size l 2 " t o 36"

Note.' For conduit size 42" to 60"

FIGURE F - 5

CANTILEVER BENT SELECTION CHART E W P Unit Portland, Oregon

bituminous filler,

ISCtMETRIC VIEW

-

/-I TYPE 2

TYPE 2

TYPE T I

The bor schedule is listed i n the opproximote order of plocement. Bors F1 through F5 ore contoined in the first pour. All reinforcing' steel i s round. St. mdons stroight.

4" preformed bituminous

BAR TYPE DETAILS

filler 10f wide.

chomfer-,

Construction joint

\ ELEVATION

NOTES

p

I 0

I: Closs "€3" concrete, *.f; =~,OOOpsi. fs=20,000 psj 2. All exposed edge; will hove inch chamfer

3

y

SECTION A-A

SECTION C-C

3. All reference t o pipe diometer is the inside diometer of the outlet pipe. 4. The bar mork numbers indicote the respective

bor locations. 5. Quantities include column and footing 6. All steel plocement dimensions ore t o center of bors.

1. W

PLAN

I

F1

I

I

I

J

;T

Bottom steel

PLAN-FOOTING I

REFERENCE: E S 105

HALF-SECTION B-B

1

Q

FIGURE F-6

CANTILEVER OUTLET BENT EWP Unit Portland, Oregon

PIPE DIA

4-0

42"

--

L

W

N

M

1-0

7-3

1-0

P

X

3-3

MARK FI F2 F3 F4 F5

5-3

SIZE SPACING d 4 1-2 0-3 4 0-llkg 4 0-Ilk 4 0-10 '

e

f

0-33,;

9

~

'

0-3'4

0-4

6

QUAN.kENGfH 4 6-9 -- 8 - 3-6 3-6 8

5

4

6-9

-2-6

-

TYPE St. St. St. St.

2

A

C

TOTAL FT. 27-0

.-: '

t-6-:

0- 6

-

B

I--0

1'

_

28-73 33-9

28-0

:

10-0

9-

6

ISOMETRIC VIEW

-?A

%==E

I

PI-

a

i

TYPE 2 BAR

fl

QUANTITIES

-

PIPE DIAMETER REINF. CONCRETE . ---

I

L N S

L-

Y ? -

-

6

L PLAN

*

-

---

REINF. ST€

NOTES I. ~loss"B"concrete. f i = 3,000 psi.

fs =20,000 psi 2. All exposed edges will hove inch chomfer 3. A11 reference t o pipe diameter is the inside diometer o f the o u t l e t pipe. 4. The bor mork numbers indicote the respective bor locations. 5. Quantities include columns,tie beom,and footing 6. All steel plocement dimensions are t o center of bors.

8

1

1

I

.

I ELEVATION

ELEVATION

4I

DETAILS

r f m ~ ? ~ m f y m e b a r schedua is listed in the opproximote order of placement Bors F I through F 5 ore contatned in <he f i r s t pour. All reinforcing steal Is round. St. is on abbreviation f o r straight.

Construction joint

I

TYPE TI. TYPE

1

_I

BOTTOM STEEL

TOP STEEL

P L A N -FOOTING

FIGURE F - 7

REFERENCE: E S 106 SECTION C - C

CANTILEVER OUTLET BENT EWP U n i t P o r t l a n d , O r e g o n

-

2 4"

3-6

4- -+7 1-9

:

B2

83 84

4 9

.

1-0 1-0

24 4 4 2

I-0

5-ll'SI0 23-6 St. -

3-0.-

23-6

st.

St

-

_ 1-5

3-1'/2 -1-5 _- ---

-- -

_._

- - .- -

- . ..

142-0 94-0 20-0

47-0

Chomfer

ISOMETRIC VIEW

SECTION

A-A

' 1 1 1I I

The bor schedule is listed in the opproximote order of plocement. All reinforcing steel irround. St. tc nn abbreviotion f o r stroight

I-

T Y P E SIO BAR TYPE

DETAIL QUANTITIES

PIPE DIAMETER

REINFORCED CONCRETE

2 4 In. -

3.26 cu. yds.

3 0 in.

4.09 cu. vds.

REINFORCING STEEL -

330.81 Ibs. 400.89 Ibs. 497.47 Ibs. 516.18 Ibs. 553.92 Ibs.

6.97 cu. yds. -- - ----.

6 0 in.

4

-

-.

SIDE

...

cu. yds. --8.06 ..- -- --. -

6 4 1 . 2 4 Ibs. 730.75 Ibs.

9.21 cu.yds.

NOTES

ELEVATION I. ~ l o s s ' b concrete, "

fk =3,OOO

p s ~ fS= 20,000 pst A l l exfosed edges wtll hove ~ n c hchomfer 3. All reforence t o pipe diometer i s th'e inside diometer o f the the outlet pipe.

q

2

4

he

outlet pipe wtll be standard strengh RIC pipe wittt o n on over-oll l e n g t h o f 2 4 f e e t .

5. Quontities include the beam only 6. The bcr mork numbers are the respective b a r locotions 7. All steel placement dimensions ore t o c e n t e r o f bars

C SIDE'

REFERENCE

ES 107

ELEVATION

FIGURE F-8

CANTILEVER OUTLET DETAIL EWP Unit Portland,

Oregon

S C A L E - 3/8"=11-0.

SCALE -

3/;$'=

1'-0"UNLESS SHOWN

=-

H A L F ELEVATION

1

S E G T ~ O NON Q

-

Bbck

,

REFERENCE

:

SECTION "A-A'

3-L-12524

--L-

DETAILS OF BENT SCALE-

we": 1'-0"

Rrv,sco 3-22-53

FIGURE F - 9

CANTILEVER OUTLET TIMBER BENT E W P Unit Portland, Oregon

u

HEADWALL ELEVATION

u SECTIONAL ELEVATION

SIDEWALL

ELEVATION

,-5Preformed p n f

filler

TABLE OF QUANTITIES l

Type of pipe

D of pipe I,

Concrete

;"preformedJ

I

--=q

'

Remf Steel

I

ASTM 7 6 8 AWWA C 3 0 2

20 21 24

1

LI

I

--

1

1 8

Steel 8 C M P

AWWA C 3 0 0 R C301

I

3.65

1 1

365 3.63

-5.bl -

13.68 3.67 366 1 3.64

1 1

3.63

1 274

Ibs

jomt f i l l e r

SECTIONAL ELEVATION Str

WINGWALL ELEVATION

BAR TYPES

SECTION

@ P. W D. BASIN SIZE D

Notes: -

PORTLAND.

Structure ,s symmetnco/ obout Chomfer exposed edges Splice length N inches

$

UNIT

mches

Class 3 0 0 0 Concrete

HALF ISOMETRIC VIEW

f, = 2 0 , 0 0 0 ps, f;; I, :

OREGON E B W P

g

3 0 0 0 ps, 1 3 5 0 PS,

PLAN

Refer to Table J - F I for refmemen1 m concrete volume

F I G U R E F-I0

-

E

P.W.D. BASIN

-

EWP Unit Portland, Oregon

....

..... - TABLE

OF QUANTITIES

Concrete Reinforcmg steel

cu yd

274

lbs

D , = m ..................................

.................. , TNe . ..............................

Traced.-~.................................

Sheel

NO

Checked ............................

~ r a w ~ nNO g

. .........it.....

.....

CONDITION I

Rock riprap not required

F -41

Conduit D i a m e t e r ( i n c h e s )

CONDITION 2 Rock riprap required When unit cost rotio of R/C to rock riprap is less than 13 use C h a r t B . I f t h e rotio is g r e a t e r than 13 compare costs o f t h e structure selected. f r o m C h a r t B with that of a contilever and armored plunge pool. 100 80

60

50 40

30

E O

D

h

[.See Figure F- 2

+

al

20

I

I\

I

I

60

72

y 2z 0

rn

-0 0

E 0

I

t

w

10 8

6.

See Figure f -/ for s i r e selection

5 . fl

4

3 8 I0

18

21

27

30

36

42

48

54

Conduit Diameter (inches)

Note: Chorts A and B opp/y for fu// conduit f /o w.

FIGURE F - l I

OUTLET STRUCTURE S E L E C T I O N CHARTS E W P Unit Port\and, Oregon

SECTION C .MISCELLANEOUS STRUCTURE Contents

. 11. 111. I V. V. I

....................... WATER LEVEL GAGE . . . . . . . . . . . . . . . . . . . . . INTAKE STRUCTURE . . . . . . . . . . . . . . . . . . . . . TIMBER CATWALK ..................... INLET-OUTLET BOX .................... INTRODUCTION

G-1 G-1 G-1 G-1 G-1

Figures

G-1 G-2

6 3

G-4 G-5

G-6

................ R e s e r v o i r W a t e r L e v e l Gage . . . . . . . . . . . . . . . . I n t a k e S t r u c t u r e With S t r a i n e r and Pylon Gate L i f t . . . . Timber Catwalk. S t r i n g e r S i z e and Cost . . . . . . . . . . Overnight Storage Reservoir: I n l e t - O u t l e t Box . . . . . . Overnight Storage Reservoir: Inlet-Outlet ......

R e s e r v o i r W a t e r L e v e l Gage

6 3

G-4 G-5 G-6

G-7 G-8

SECTION G

I.

-

MISCELLANEOUS STRUCTURES

INTRODUCTION A wide v a r i e t y of m i s c e l l a n e o u s s t r u c t u r e s have been d e s i g n e d f o r i n d i v i d u a l s i t e c o n d i t i o n s . S e v e r a l t h a t l e n d themselves t o r e p e a t e d u s e a r e i n c l u d e d f o r c o n s i d e r a t i o n by t h e d e s i g n e r .

11. WATER LEVEL GAGE Both t h e t r e a t e d t i m b e r and t h e s t e e l w a t e r l e v e l gage, a r e set f l u s h w i t h t h e upstream s u r f a c e of t h e embankment. E l e v a t i o n o r s t a g e markings s h o u l d b e d e l a y e d u n t i l t h e i n i t i a l embankment s e t t l e m e n t h a s t a k e n p l a c e . 111. INTAKE STRUCTURE

The p y l o n t y p e g a t e l i f t ( F i g u r e G-3) i s n o t recommended f o r c o n d i t i o n s where i c i n g i s s e v e r e . Access t o t h e p y l o n i s by b o a t d u r i n g most r e s e r v o i r s t a g e . IV.

TIMBER CATWALK T h i s i n s t a l l a t i o n i s n o t recommended f o r c o n d i t i o n s where i c i n g i s s e v e r e . F i g u r e G-4 p r o v i d e s a f a s t approximate c o s t used f o r a l t e r n a t e comparison. Although t h e catwalk width i s only 2 f e e t , t h e b a s i c d a t a w i l l allow f o r w i d t h i n c r e a s e more d e s i r a b l e f o r r e c r e a t i o n a l p u r p o s e s . See F i g u r e H - 3 f o r t y p i c a l l a y o u t d e t a i l f o r t h e c o n s t r u c t i o n drawing. A h a n d r a i l i s recommended and can b e added by e x t e n d i n g t h e decking a t about 8 f o o t centers t o provide brace support f o r the handrail posts.

V.

INLET-OUTLET BOX F i g u r e s G-5 and G-6 p r o v i d e b o t h d e t a i l s and p r o p o r t i o n s f o r a s m a l l r e s e r v o i r i n l e t - o u t l e t box. The r e s e r v o i r i s f i l l e d by pumping d u r i n g o f f peak p e r i o d s . A combination o f pumping and r e s e r v o i r d i s c h a r g e can b e used f o r peak r e q u i r e m e n t s .

5"

IT x 6" l a g screw and washer

PLAN

SECTION

llll 1 I 1111

Creosoted posts

@

Locate gage on the upstream of dam, normal to the the face of the gage flush with the outer surface. Place posts on alternate sides o f the gage plank. Establish elevations o r stage according to reservoir survey datum and mark with permanent and easity visible materials.

ELEVATION

WATER LEVEL GAGE

F I G U R E G-I

RESERVOIR WATER L E V E L GAGE EWP Unit Portland, Oregon

I"

Graduate gage to 0.10 ft. Elev. with 3 deep marks a shown. Paint elev. numerals from E l e v . 6 la lev.

0

N UI

I

I

I

I

I

I

I

6 , ru,

+

3" pipe

PLAN

SECTION

@

ocate gage on the

f ~ l lsurface. Establish elevations or stage according to reservoir survey dotum ond 'mark with permanent grooves or weld beod. Paint figures far easy

ELEVATION

WATER LEVEL GAGE

FIGURE G - 2

RESERVOIR WATER LEVEL GAGE EWP Unit Portland, Oregon

Q

Q

0

0

0

0

0

PLAN

Stem

STEM GUIDE See Figure D- l for stem g u i d e spacing

Vent pipe

C

Typical lower brace 2 " galv. pipe

Screen- s t e e l pipe ~ e r f o r a t e dto 150% of 'pipe area with I" holes @ 3" c - c. Galvqnize after fabricating.

.-

p:;=3~ ~ e ~ o ~ o ~ ~ * ~ O * a ~ l l ~ Flange may be notched for insertion of bolts.

ELEVATION FIGURE G-3

I N L E T STRUCTURE WITH STRAINER AND PYLON GATE LIFT EWP Unit Portland, Oregon

STRINGER,

POSTS 2"x 6" Notes: I. Multiple story bents to be used for heights in excess of 14'-0". 2. Costs do not include mechanical features of the gate system. 3. Allowable working stress, f = 1 2 0 0 p.s.i. 4. Timber quantity includes substructure and deck.

2 x 12

21-o'1210ll

r-k-i

Timber Construction Cost

I

@$400/MFBM

2

3

Timber Quantity- MFBM

FIGURE G-4

TIMBER CATWALK: STRINGER SIZE, AND' COST EWP Unit Portland, Oregon

4

4

PLAN OF OUTLET

Cutoff collars of fabricated steel may be used instead of'concrete. Sleel placement, #@/2"center to center bothways. All s,dices 30 bar diameters. Under highly corrosive condifions pipe shall be asphalt dipped. Adequately protected earth spillway may .be substhtbd f6r drop box. PuMp may discharge over top of box, Instead of using flap gate. Location of inlet and out/ets should vary to meet locd conditions. Ernbonkment design $ha// camp& with criteria as set forth in Tech. Memo. Soil Mechanics Series No. 3 B No. 4. Max. height of embankment l5'-0" Maderote or hioh hazard locatims shall require o goje on the upstreom end of the outlet pipe. See Engrr Memo No. 3 ,for defin,tions and for other r ~ s t r i c t ~ ncqr ~ t e r ~ o .

SECTION

OUTLET BOX

CUTOFF COLLAR

FIGURE G - 5 REFERENCE:

7- L- 20090

OVERNIGHT STORAGE RESERVOIR INLET-OUTLET BOX E W P Unit Portland, Oregon

1

40

-16; I

I

I

6"

L

I .

- 'L 4'-0" I

1-

PLAN

:*

Lf1

-€&

Use /urger '1'' vo/ue required fo; either vuriuble 'hor D

SECTION ON CENTERLINE

---- *--..24

0 1 .

aJ

. BAFFLE PERSPECTIVE

-.18

ALTERNATE BAFFLE DETAl L Alternate baffle limited to 18" gate size. Baffle consists of welded steel pipe, or surplus hot water tonk w~thends cut off. Gate size opening, cut in side, is positioned,, over outlet and assembly ,,is fastened to heodwall with two bars with threaded ends U " shoped to fit baffle.

+

w

E .o aJ C

0

.. w

-us--

:..

-- 12

r

5

FIGURE G - 6 REFERENCE 7-L- 20090

OVERNIGHT STORAGE RESERVOIR INLET- OUTLET B O ~ EWP U n ~ tPortland, Oregon

SECTION H

.DRAWING

LAYOUT AND SUMMARY

Contents I.

. 111. I1

IV

.

. VI . V

................... DETAILSIZE . . . . . . . . . . . . . . . . . . . . . . . . DRAWING DEVELOPMENT . . . . . . . . . . . . . . . . . . . . SUMMARY SHEET .........*............ EXAlviPLE . . . . . . . . . . . . . . . . . . . . . . . . . . SUMMARY SHEET . . . . . . . . . . . . . . . . . . . . . . . REPRODUCTION PROCESS

Page

H-1

H-1 H-1 H-2 H-3 H-5

Figures H-1

T y p i c a l Layout

H-2

T y p i c a l Layout

H-3

T y p i c a l Layout

H-4

T y p i c a l Layout

H-5

T y p i c a l Layout

............ .S t r u c t u r a l D e t a i l s . . . . . . . . . . . . .I n l e t S t r u c t u r e Example . . . . . . . . . .S t r u c t u r a l D e t a i l s Example . . . . . . . . .O u t l e t D e t a i l s Example .........

.S t r u c t u r a l

Details

H-9 H-11 H-13 H-15 H-17

SECTION H

-

DRAWING LAYOUT AND SUMMARY

The end r e s u l t o f o u r d e s i g n i s t o d e v e l o p a s e t o f c o n s t r u c t i o n drawings from which t h e s t r u c t u r e c a n b e b u i l t . I n s e l e c t i n g the p r o p e r d e t a i l s c a l e s , t h e r e p r o d u c t i o n p r o c e s s t o b e used s h o u l d b e known i n advance. I.

REPRODUCTION PROCESS Two methods o f p r i n t i n g c o p i e s of t h e drawings a r e commonly used. The most common method f o r s m a l l j o b s where a l i m i t e d number o f p r i n t s a r e t o b e made i s t h e o z a l i d p r o c e s s . No change i n s i z e from o r i g i n a l t o p r i n t i s i n v o l v e d . F o r l a r g e r j o b s o r where a g r e a t e r number, 30 o r more, c o p i e s a r e t o b e made a l i t h o g r a p h i c p r o c e s s i s used. P r i n t i n g p r e s s e s f o r t h i s process a r e limited i n s i z e , requiring a reduction i n p r i n t s i z e from t h e o r i g i n a l normal "E" s i z e drawing t o a s m a l l e r "N" size. The s m a l l e r s c a l e drawings are u s e d p r i m a r i l y f o r i n f o r m a t i o n t o b i d d e r s w h i l e t h e l a r g e r drawings would b e used f o r c o n s t r u c t i o n depending on t h e amount o f d e t a i l on t h e drawing.

11.

DETAIL SIZE The c h o i c e o f s c a l e u s e d w i l l depend on t h e r e p r o d u c t i o n p r o c e s s and complexity o f t h e d e t a i l . L e g i b i l i t y and c l a r i t y a r e e s s e n t i a l . I n some c a s e s a p e r s p e c t i v e o r i s o m e t r i c view i s a d v i s a b l e . L e g i b i l i t y depends upon t h e r e a d e r ' s a b i l i t y t o d i s t i n g u i s h t h e f e a t u r e s and r e a d t h e l e g e n d w i t h o u t v i s u a l d i f f i c u l t i e s . T h i s a b i l i t y v a r i e s among p e o p l e depending upon e x p e r i e n c e and eyes i g h t . C l a r i t y , as opposed t o l e g i b i l i t y , i s a s s o c i a t e d w i t h u n d e r s t a n d i n g and depends o n d e t a i l . C l a r i t y v a r i e s more w i t h t h e experience of t h e r e a d e r than w i t h eyesight. The drawings s h o u l d b e o f a s c a l e and d e t a i l t o convey t h e i d e a t o a b u i l d e r w i t h normal v i s i o n and e x p e r i e n c e commensurable w i t h t h e c o m p l e x i t y o f t h e p r o j e c t . Keep i n mind i t i s e r r o n e o u s t o assume a l a r g e r s c a l e makes d e t a i l s e a s i e r t o r e a d and understand. The above r e a s o n i n g was used i n e s t a b l i s h i n g t h e s c a l e s t o b e used f o r t h e d e t a i l s i n t h i s manual. S t e e l schedules, stem s p l i c e s and t i t l e s h a v e beeri i n c l u d e d i n two s c a l e s where a p p l i c a b l e ; each c o n s i s t e n t w i t h t h e f i n a l r e p r o d u c t i o n process t o b e used.

111.

DRAWING DEVELOPMENT

Other than t h e s t a n d a r d drawings, p r e p a r a t i o n of t h e o r i g i n a l

drawings f o r a p a r t i c u l a r job may b e by one o f two methods: (1)

D e t a i l s i n t h e a p p r o p r i a t e s c a l e from t h i s book may b e t r a c e d - d i r e c t l y on t r a c i n g p a p e r i n t h e arrangements a s shown on F i g u r e s H-1 and H-2, o r

(2)

A "mock up" of each c o n s t r u c t i o n drawing can b e made by u s i n g d e t a i l s h e e t s s i m i l a r t o t h o s e i n t h i s book, c u t t i n g o u t t h e a p p r o p r i a t e p a r t s and t a p i n g them d i r e c t l y t o B r i s t o l b o a r d i n t h e s u g g e s t e d l a y o u t . I f t h i s p r o c e s s i s used i t s h o u l d b e done i n t h e C a r t o g r a p h i c U n i t . From t h i s "mock up" a n 8" x 10" n e g a t i v e w i l l b e made and f i n a l l y an "E" s i z e f i l m p o s i t i v e , which s e r v e s a s t h e f i l e copy. Chronoflex p o s i t i v e s have a mat: s u r f a c e t h a t w i l l t a k e p e n c i l o r i n k i f any changes o r a d d i t i o n s a r e t o b e made.

I n e i t h e r method, " f i l l - i n " b l a n k s and s p e c i a l d e t a i l s w i l l r e q u i r e i n d i v i d u a l a t t e n t i o n . Information regarding t h e component p a r t s may b e t r a n s m i t t e d on s h e e t s s i m i l a r t o F i g u r e s H-1 and H-2. The a p p r o p r i a t e s t a n d a r d drawing o r d e t a i l number s h o u l d b e l i s t e d i n each b l o c k o r completed summary s h e e t s w i l l . p r o v i d e more complete i n f o r m a t i o n t o t h e draftsman. A s k e t c h of s p e c i a l d e t a i l s s h o u l d b e i n c l u d e d .

IV.

SUMMARY SHEET

A summary form c o n s i s t i n g of f o u r pages w i t h f i l l - i n b l a n k s h a s been developed t o s e r v e s e v e r a l n e e d s . P r o p e r l y f i l l e d i n , t h e summary s h e e t s w i l l b e a: (1)

Convenient check l i s t o f i n f o r m a t i o n needed f o r development of t h e d e t a i l s .

(2)

Document t h e d e s i g n d e c i s i o n s .

(3)

Concise form f o r t r a n s m i t t a l o f i n f o r m a t i o n t o t h e draftsman f o r completion o f t h e c o n s t r u c t i o n drawings.

A d d i t i o n a l s h e e t s s h o u l d b e added, a s needed, t o p r e s e n t t h e s p e c i a l d e t a i l s f o r t h e p a r t i c u l a r job. Completed summary s h e e t s have been i n c l u d e d i n t h e example i l l u s Data e n t e r e d on t h e t r a t i o n , i n t h i s s e c t i o n , pages H-5 t o H-8. s h e e t s has been p r i n t e d i n red t o d i s t i n g u i s h t h e information t h a t w i l l vary from job t o job. S e c t i o n s t h a t do n o t apply t o t h e g i v e n job have been voided (by l a r g e c r o s s ) t o s i m p l i f y review.

EXAMPLE

The problem from t h e p r e v i o u s s e c t i o n s h a s been extended f o r t h e 21" c o n c r e t e p i p e t o show t h e completed reduced s i z e drawing i n F i g u r e s H-3, H-4 and H-5. F i g u r e H-3 i s t h e s t a n d a r d i n l e t s t r u c t u r e , S i z e H , completed f o r t h e 21" c o n d u i t . F i g u r e H-4 i s made up o f a p p u r t e n a n t d e t a i l s u s i n g t h e mosaic p r i n c i p l e and a p h o t o g r a p h i c p r o c e s s . F i g u r e H-5 i s a s t a n d a r d impact b a s i n drawing, S i z e C , completed f o r t h e 21" c o n d u i t . T h i s f i g u r e i s t o b e r e p l a c e d w i t h s t a n d a r d drawing ES-4070-040 when a v a i l a b l e . A l l of t h e example drawings were 21" x 30" reduced t o t h e i r present size.

To complete t h e c o n s t r u c t i o n drawings f o r t h e a p p u r t e n a n c e s , a n embankment p r o f i l e through t h e c o n d u i t w i l l b e r e q u i r e d . The r e l a t i v e p o s i t i o n s of t h e appurtenances s h o u l d b e shown on t h i s p r o f i l e u s u a l l y l o c a t e d on t h e same s h e e t a s t h e p l a n of t h e dam ( n o t i n c l u d e d i n t h i s example).

-

s TATE

GATED

/Dft

/nu -

Em. Sp. E l . Pr. Sp. El.

JOB NO.

-/id-48

, , , ,

OUTLET APPURTENANCES SUMMARY SHT.

GIVEN :

El.

lm

BY

PXM

HWf SUBJECT

AHo~Rfj~r/d+

PROJECT CHECKE

OUTLET TYPE

1H.f

Conduit length

C r i t i c a l design ft H-

Q

2P 4P

131 -.

f t.

Foundation s o i l type d C Jbbankment s o i l type

cfs

Q-

C

GC

SELECTED

INLET

?/

Conduit s i z e Gate

Fig. C - 1

Fig. C-2 Fig. C-2 C-3

a

Impsc t les SAF 0 Extended l i n e 0

--

/

4

/

Diameter Size 8/ Type back Flat Spigot E Flange Other

Std. Drawing No. 7 6 - 2 0 4 6 5

inches

117'0

class

A B C D E F C@

I J

Trash rack

fUp/ps

Longitudinal members Cross b a r s s i z e

C l i p height

Single

z

4*

Double

FAa W W

By

/wf

SUBJECT

~ k mRCJZ,,VQI'~ cHEc~AS' /-4-68 PROJECT

STATE

I

DA f E

1-15-68

DATE

JOB NO.

GATED OUTLET APPURTENANCES SUMMARY SHT

F i g . C-5

Rock protection

Fig. C-6

Vent pipe diameter

2

R "75 Rock layer thickness Filter layer thickness

Vechanical kf Hydraulic

Type of control

r

Fig. D-1

7-L-20544 A B

Lift pedestal size

diameter

Lift Types

Lift nut Ball bearing 15" geared crank ratio

[

Material

stem

Pig. D-6, 7, 8

-

Bronze 0

Diameter Encasement Stem pedestals: spacing Gate stem guide type

L -

Fig. D-2f

Fig. D-21

Operation pressur

Fig. D-24

Compare Alternate 0

0D E F

19 in. cast iron bronze ha no yes

Stainless

in;:eh

16 ft Number channel welded 0 cast U

CR

4

B Y SUBJECT

~

I

Rk,,trmL? rHECRd lDATF/l - 48 PROJECT

bfh7 --

s T A T E ~- - -

DA E ~

AS-68 ~

,4/im

GATED OUTLET APPURTENANCES

SUMMARY

SHT

H -7 JOB NO.

, , , ,

3

,,4

CONDUIT Conduit type:

Metal

gage

0

monolithic

R/C

F i g . E- 2

inches long.

t

rebar Precast

trans.

0 0

AWWA C300 AWWA C301

8

AWWA C302 other

Anti-seep c o l l a r s , increase i n creep length 'X 1 5 0 2 0 0

Fig. E- 8

L

/J1I' H I

Number of collars

Fig. E-12

Outlet type:

v Z*P' 6

SAP Cantilever Concrete Bent Steel & timber

a

Earth

a

Armored

D

Fig. F-2

Impact basin

Fig. F-1

WJD s i z e

Other

F i g . G-1

Fig. G-3

Intake strainer

ES

74-20463

Standard0

Fig, 6-2

0 ther

17

4#70 A B C D E F G H

Modified

1 0 2 0

H-8

STATE

FAk

H'F

BY SUBJECT

mr

PROJECT

IoAf.?f- 68

A/hm DATE &tvuol'r

/+' - Lg

CHECKED BY

FKM

GATED OUTLET APPURTENANCES

SUMMARY SHT

JOB NO.

,,,,,

4

RAWING LAYOUT

Drawing s i z e :

Full

0

Reduced

Department Of Conservation And Development, Division Of Flood Control APPLICATION No. APPROVED AS TO SAFETY: DATE: S U P E R V I SOR

" I am hereby submitting for approval this plan as an officer of the United States Government authorized to approve and submit such plans." State Soil Conservation Engineer. So'il Conservation Service

4

STEEL SCHEDULE Selec f from Figures 0 - 15, 0-16, 0-17

Se lect from figures E- 3, E- 4

R/C Conduit and Collor Gote Stem Pedestal Gate L i f f Pedesfol

ANTI -SEEP COLLAR

HANDWHEEL BRACKET OR BAS^ PLATE Select from Figures C - 2 , C - 3

TRASH RACK DETAILS

STEEL LAYOUT See Fig D - 5

STRUCTURAL LAYOUT

Se/ect from sizes A fhru E See Figures 0-10 thru 0-14

See Fig. 0- 5

Select from Figures D - 6 , D - 7,D - 8

STATE APPROVAL BLOCK

T I T L E BLOCK GATE STEM PEDESTAL

GATE LIFT PEDESTAL

FIGURE H-l

GATE STEM GUIDE

-

TYPICAL ,LAYOUT STRUCTURAL DETAILS EWP Unit Portland,Oregon

STEEL SCHEDULE Gate Stem /n/ef

/$fipe

.

0 SCALE

5

10 IN

15

FEET

,,

VENT PIPE CONNECTl0,N 4T X

INLET STRUCTURE

STATE APPROVAL BLOCK Inches

3

SCALE

Feet

TITLE BLOCK FIGURE H - 2 I

GATE STEM GUIDE

T Y P I C A L LAYOUT STRUCTURAL DETAIL: E W P Unit Portland, Oregon

SECTIONAL ELEVATION

SECTIONAL ELEVATION

SECTIONAL ELEVATION

TOP F A C E

Sfr

IA BOTTOM

B

.I

FACE

PLAN

UPSTREAM ELEVATION DOWNSTREAM ELEVATION BAR TYPES

Department Of Conservation And Development, Division Of Flood Control APPLICATION No. APPROVED AS TO SAFEW. DATE: s"?ER",-"n

INLET

STRUCTURE

P O R T L I N D OREGON

SIZE H

E B W P UNIT

INLET STRUCTURE

ALDAM RESERVOIR 4; s','

PLAN

HOOD S.C.D.

ISOMETRIC VIEW

Rock riprop as r e q u ~ r e d

TOYA COUNTY, OREGON

U. S. DEPARTMENT OF AGRICULTURE SOIL CONSERVATION SERVICE I

0

SCALE

5

IN

FEET

" I am hereby submttting for approval this plan as an officer of the Unlted States Government authorized to approve and submit such plans."

HWF Derlgned............. Draw"....

LLLJ

Tm~ed.............. Slate Sod C O ~ I ~ I Y Engmter, ~ I C ~ ~ Soil Conrervatm S e r n n

FIGURE H-3

INLET STRUCTURE

STEEL

I.

Str

8

SCHEDULE

CJ

2- $"x 1 2 Anchor bolts

ELEVATION

\

6 onfl - seep collars reowred

One layer of heavy, smooth surface, asphalf treated, roofing f e l t Appror wf 55 lbs p e r square

ELEVATION

BAR TYPES

SECTION

Note. F d l w ~ t hS A E PO molor o ~ l ,

ANTI - SEEP COLLAR I

5

0

Ploce weather seal above ripropped sectmn clear of conlrol structure

T -SCALE

PLAN

DETAILS

TRASH RACK Not to Scaie

DETAIL OIL S E A L

GATE STEM GUIDE Not to Scole

D i o g o l e stem "

1

SECTIONAL ELEVATION

SlDE E L E V A T I O N

SECTIONAL E L E V A T I O N

~5'>3"xg 2'-3"long

TOP FACE

fweomer sea/\

,

SECTION

@

~ i sot e m ' i / " b o l l

I

I

ELEVATION

1

-

onchorbolt

1

Y

SlDE VIEW

I

,a,

Department Of Conservation And Development, Division Of Flood Control

APPLICATION No. APPROVED DATE: AS TO SAFETY:

I Y I Z I Y I %OR

" I am hereby submitting for approval this plan as an officer of the United States Government authorized to approve and submit such plans."

SUPPORT ANGLE DETAIL

I

STRUCTURAL DETAILS

ALDAM RESERVOIR HOOD S.C.D. TOYA

PLAN

PLAN

-

PLAN

GATE STEM PEDESTAL

GATE LIFT PEDESTAL

5

0

IN

FEET

COUNTY.OREGON

I U.S. DEPARTMENT OF AGRICULTURE SOIL rnNcnnv A nnN c n n x n m FIGURE H - 4

PLAN

GATE STEM SPLICE .Not to Scale

Drawn ............ ...

STRUCTURAL DETAILS

Traced --.--..-.....-

cnemed

.FX.M

....

EWP U n i t P o r t l a n d , O r e g o n

~

SIDEWALL

T R JOINT

.

SEC. @

ELEVATION

SEC.

@ BAR TYPES

SECTIONAL

ELEVATION WINGWALL

ELEVATION

" I am hereby submitting for approval this plan as an officer of the United States Government authorized to approve and submit such plans."

Department Of Conservation And Development, Division Of Flood Control

TO BE REPLACED BY DRWG NO E S 40700040

BAFFLE WALL

APPROVED ASNo. APPLICATION TO S A F W DATE:

IMPACT

BASIN

SIZE C

PORTLAND.OREGON E 8 W P UNIT

I

OUTLET DETAILS

ALDAM RESERVOIR HOOD S.C.D. TOYA COUNTY, OREGON

PLAN

SCALE

IN

FEET

1

TABLE

OF QUANTITIES

Concrete

Remforcing steel

cu yd

bs

HALF PERSPECTIVE VIEW

I

!E!..........

mwmd. . . .

Drawn . . . . . . . . . . . . . . . . . . . . .

Traced

LL,'( .......................

checked

!"!C

.....

............4

FIGURE H-5

IMPACT BASIN EWP Unit Portland, Oregon

SECTION I

-

BIBLIOGRAPHY

Contents

.......................... . ComrnercialCatalogs . . . . . . . . . . . . . . . . . . . . . . . General..

Page 1-1 1-2

SECTION I

-

BIBLIOGRAPHY

Albertson, M. L.; Dai, Y. B.; Jensen, R. A.; and Rouse, H. iffus us ion of Submerged Jets," Transactions of the American Society of Civil Engineers, Volume 115, 1950, pp. 639-697. American Concrete Institue, "Erosion Resistance of Concrete in Hydraulic Structures,'' ACI Committee 210, Title No. 52-18, pp. 259-271. Armco, "Handbook of Water control," Lederer, Street, and Zeus Co., Inc., Berkeley, California, 1946 pp. 383-512. Arque, J. R., Discussion of "Hydraulic Design of Stilling Basins: Small Basins for Pipe or Open Channel Outlets - No Tailwater Required (Basin VI)" by Bradley, J. N. and Peterka, A. J., ASCE Proceedings Paper 1406, October 1957. Discussion appears in Journal of the Hydraulics Division, Volume 84, No. HY2, April 1958, pp. 1616-77 to 1616-91. Ball, J. W., "Cavitation Characteristics of Gate Valves and Globe Valves," Transactions of the American Society of Mechanical. Engineers, Volume 79, No. 6, August 1957, pp. 275-81. Ball, J. W., "Limitations of Metergates," Journal of the Irrigation & Drainage Division, Proceedings Paper No. 3359, December 1962. Ball, J . W. "Hydraulic Characteristics of Gate Slots," Journal of the Hydraulics Division, ASCE, Volume 85, HY10, October 1959, pp. 81-114. Blaisdell, F. W., "The SAF Stilling Basin," Soil Conservation Service, SCS-TP-79, May 1949, pp. 1-14. Hall, L. S., Kalinske, A. A., & Robertson, J. M., "Entrainment of Air in Flowing Water, A Symposium," wi'thdiscussions, Transactions of the American Society of Civil Engineens, 1943, pp. 1393-1516. Joint Industry Cderence. "Hvdraulic Standards for Industrial Equipment," Hydraulics and Pneumatics, 1959, pp. R-1 to R-30. Bureau of Reclamation, "Design of Small Dams," U. S. Government Printing Office, Washington, D. C., pp. 291-311, 326-372, 456-459. Bureau of Reclamation, "Turbines and Pumps ,'I Commissioners Off ice, Denver, Colorado, Design Standards No. 6, 1957, Chapter 7, Figure 68. Bureau of Reclamation, "Valves, Gates and Steel Conduits," Design Standards No. 7. Bureau of Reclamation, "Hydraulic Design of Stilling Basins and Energy Dissipaters," Engineering Monograph No. 25, Commissioner's Office, Denver, Colorado.

Bureau of Public Roads, "Hydraulic Charts for the selection of Highway Culverts", Hydraulic Engineering Circular No. 5. Corps of Engineers, U. S. Army, "Hydraulic Design criteria," Waterways Experiment Station. "Handbook of Steel Drainage and Highway Construction Products," American Iron and Steel Institue, New York, New York, 1967. Mechanical Engineer's Handbook, Lionel Marks, Fifth Edition, 1951. Soil Conservation Service, "Hydraulics," National Engineering Handbook, Section 5. Soil Conservation Service, "Structural Design," National Engineering Handbook, Section 6. Soil Conservation Service, "Chute Spillways," National Engineering Handbook, Section 14. Soil Conservation Service, "Engineering Practice Standards," Part I, National Engineering Handbook, Section 2. Soil Conservation Service, "Earth Spillways," Technical Release No. 3. Soil Conservation Service, "Height of Water Column Supported by Atmospheric Pressure," Technical Release No. 4. Soil Conservation Service, "Engineering Design Standards States .I1

-

Far West

Soil Conservation Service, "Specifications For Construction Contracts," National Engineering Handbook, Section 20. Commercial Cataloes Armco, "Armco Water Control Gates Catalog," Armco Drainage & Metal Products, Inc., Middletown, Ohio, Catalog G-3263, 1963. Carter Fluid Power Controls, Bulletin 3000B, Series S, Carter Controls, Inc., Lansing, Illinois. Rodney Hunt, "Sluice Gates," Rodney Hunt Machine Company, Orange, Massachusetts, Catalog No. WC160, 1960.

-

SECTION J

APPENDIX

Contents

Page

CRITERIA AND PROCEDURE FOR DESIGN OF THE STANDARD PWD BASIN

11.

DESIGN CONSIDERATIONS AND METHOD OF ANALYSIS

5-2

Tables J - C 1 Q u a n t i t y Survey f o r I n l e t S t r u c t u r e 11

J-Dl

I'

J-D2

"

J-El

I'

J-E2

"

11

J-E3

"

11

.

.......... .............

J-6

L i f t Pedestals

5-6

11

It

11

"

R / C ~ o n o l i t h i cConduit

e

I.

R/C Anti-Seep

.........

"

'I

I1

J-E5

"

11

J-E6

"

11

"

Collars

.

.

.

.

.

It

I'

"

.

.

5-7

.

J-9

Conduit C r a d l e Type A 1 o r A2 Dams L e s s Than 50 F e e t High * . . . a * . . . . .

J-10

Conduit C r a d l e Type B 1 Bedding

J-11

. ..

Anti-Seep C o l l a r s f o r Type A l and A2 C r a d l e s f o r Dams C l a s s ( a ) Over 50 F e e t High and C l a s s ( b ) and ( c )

5-12

Anti-Seep C o l l a r s Type A 1 and A2 C r a d l e s For Dams C l a s s (a) Less Than 50 Feet High

5-13

Anti-Seep C o l l a r s Type B1 Bedding f o r Dams C l a s s (a) Over 50 Feet High and C l a s s (b) and (c)

5-14

Anti-Seep C o l l a r s Type B 1 Bedding f o r Dams c i a s s (a) Less Than 50 Feet High

J-15

.

...........

II

11

"

It

5-8

Conduit C r a d l e Type A l o r A2 Dams C l a s s ( a ) Over 50 Feet High and C l a s s (b) and (c)

..

11

J-5

Gate S t e m ' P e d e s t a l s

0

J-E4

.

9

Impact Basin

.

.

..

5-17

SECTION J

-

APPENDIX

C r i t e r i a and P r o c e d u r e f o r t h e Design o f S t a n d a r d PWD O u t l e t S t r u c t u r e s I.

CRITERIA A.

For g e n e r a l p r o p o r t i o n s and p r o f i l e : Refer t o ASCE J o u r n a l o f t h e H y d r a u l i c s D i v i s i o n , Vol. 8 4 , No. HY2, A p r i l 1958, P a r t I , pages 1616-77 t o 91. D i s c u s s i o n by J . R. Argue of p a p e r , "The H y d r a u l i c Design o f S t i l l i n g B a s i n s , Small B a s i n s No T a i l Water Required" f o r P i p e o r Open Channel O u t l e t (Basin V I )

.

B.

C.

-

L i m i t a t i o n s on u s e o f s t a n d a r d p l a n s .

-

1.

Pipe v e l o c i t i e s (pipe e x i t o r o u t l e t s t r u c t u r e entrance) Maximum a l l o w a b l e v e l o c i t y i s a s s o c i a t e d w i t h a n e q u i v a l e n t head o f t h r e e c o n d u i t d i a m e t e r s a t f u l l p i p e f l o w , e x c e p t f o r c o n d u i t d i a m e t e r 18 i n . and smaller. Although n o t recommended, where t h i s t y p e o f b a s i n i s t o b e u s e d f o r heads i n excess of 3d, a longer b a s i n w i l l be required t o contain the jet. To s i m p l i f y t h e number o f s t a n d a r d s t r u c t u r e s , t h e length of next l a r g e r s t r u c t u r e is t o be checked f o r jet t r a j e c t o r y . Although a d d i t i o n a l w i d t h i s wasted, r e f i n i n g the e n g i n e e r i n g a n a l y s i s i s n o t j u s t i f i e d on t h e b a s i s o f economy,

2.

Tailwater - adequate t a i l w a t e r depth i s required t o a s s u r e d i s s i p a t i o n of j e t e n e r g y and d i f f u s i o n of t h e f l o w t o distribute it across the e x i t sill.

3.

I n u p l i f t from h i g h groundwater c o n d i t i o n s , s p e c i a l backf i l l o r design modification is required.

S t a n d a r d i z a t i o n o f s t r u c t u r e s i z e : The f o l l o w i n g s t r u c t u r e s i z e s w i l l c o v e r a wide range of c o n d u i t s i z e s and d i s c h a r g e capacity

.

Size

-1/

Conduit D i a . In.- 1/

2 /31 -

-4 /

~ e n ~ t h 1 . I ~ i d t h l ~ Cutoff-4 /

F u l l p i p e flow. The l e n g t h and w i d t h a r e a f u n c t i o n a f a f i x e d sidewall flare. C u t o f f i s t o t a l h e i g h t o f downstream t r a n s v e r s e s i l l .

D.

Allowable Stresses

1, Concrete f'c fc

3000 psi 1350 psi

= =

2. Reinforcing fs = 20,000 psi Shrinkage and temperature steel p

3.

=

0.0025 in each direction

Earth bearing pressures Passive 2.0 200 silty clay Rock riprap required downstream of the cutoff for a distance equal to 4 x conduit diameter. =

=

E.

Loads 1.

Lateral soil pressure

EFP K,

=

65 pcf

=

0.5

2. Sliding resistance f

=

0.33 masonry on clay

DESIGN CONSIDERATIONS AND METHODS OF ANALYSIS

11.

'

The selection of the PWD basin in preference to other types of outlets is based primarily on economic consideration within the range of hydraulic and site limits. As an irrigation outlet this structure will be used under controlled outflow conditions. Its size selection is not necessarily based on the total available head at full pipe capacity but more likely at a Q that is maintained fairly constant over a range of heads by means of gate control. If the maximum p~ssibledischarge is to be passed through the structure, the structure should be sized for this discharge or added protection provided downstream of the structure for the short duration maximum flow. Tailwater and downstream channel stability (erosion) must be predictable.

A.

B.

Structural elements 1.

Sidewalls and headwalls are designed as horizontal and vertical beams divided by an assumed 45O boundary line.

2.

Apron or slab is designed as a rigid U section.

Stability 1,

Sliding - with the use of a downstream cutoff wall as listed in the "Standardized Structure Size" and with the use of rock riprap in the channel, no sliding problem is anticipated.

2*

Overturning

3.

Uplift - special backfill material and drainage facilities are required in site conditions with high water table.

-

no anticipated problem.

Table J-C1

QUANTITY SURVEY FOR INLET STRUCTURE

Conduit Inside Diameter

Structure Size

I

in.

IASTM-C~ASTM-C~ I Reinforcing Steel

- - - -

I

Type of Pipe AWWA C300 Welded Steel 6( CMP AWWA C301

I 1

Concrete Volume

TABLE J-Dl QUANTITY SURVEY FOR GATE STEM PEDESTAL

0.10 cu yd

Concrete volume

13.68 lb

Reinforcing steel

TABLE J-D2 QUANTITY SURVEY FOR GATE LIFT PEDESTAL

Structure Size

Concrete Volume cu yd

Reinforcing Steel1L

TABLE J - E l

QUANTITY SURVEY FOR R/C MONOLITHIC CONDUIT (Cu yd p e r l i n e a l f o o t ) Conduit Inside Diameter D - inches

6

8

12

15

18

21

24

8

0.090

0.135

-

-

-

-

-

12

0.119

0.173

0.304

-

-

-

-

15

0.142

0.202

0.346

0.475

-

-

-

18

0.166

0.232

0.388

0.527

0.685

-

-

21

0.191

0.263

0.432

0.580

0.747

0.932

-

24

0.217

0.295

0.476

0.634

0.810

1.004

1.217

30

0.272

0.362

0.568

0.744

-

0.939

1.152

1.383

36

0.331

0.436

0.664

0.859

.

1.072

1.303

1.553

42

0.394,

0.509

0.764

0.977

1.208

1.458

1.727

Thickness

-

t - inches

TABLE J-E2 QUANTITY SURVEY R/C MONOLITHIC CONDUIT ANTI-SEEP COLLARS

fV=

I

Note:

Minimum projection of cutoff from conduit casing-ft .

Top figures are concrete volumes in cu yd; bottom figures are steel quantities in lb. Steel quantities are based on a maximum bar spacing on 12 in. center to center.

Two burs Three bars

11

Two bars.

2/ -

Three bars.

-

1

TABLE J-E3 QUANTITY SURVEY CONDUIT CRADLE TYPE A1 or A2 FOR DAMS CLASS (a) OVER 50 FEET HIGH AND CLASS (b) and (c) (per foot conduit length)

Type,

ASTM C-76

Conduit Inside Diameter inch

I

ASTM C-361 AWWA C-300 Reinforcing AWAC-302 AWWAC-302 Stee1 onl$(f;=6000 psi) ;fr=4500 psi) (Type ~1 Concrete Volume cu yd I cu yd lb

1

12 15 16

1 -

of Conduit

I

I

AWWAC-301-1

1

cu yd

I

AWWA C-301 ordinarily not available in diameter less than 42".

L

L%@ IZ.MAYXSE S ~ R A I G H T $ 0 BUT NOT LESS THAN 6 A1 C R A D L E

A2 CRADLE

TABLE J-E4 QUANTITY SURVEY CONDUIT CRADLE TYPE A1 AND A2 FOR DAMS LESS THAN 50 FEET HIGH (per foot conduit length)

Conduit Inside Diameter

Reinforcing Stee1 (Type A 1 only)

inch

-1/

I

Ib

Type of Conduit ASTM C-76 ASTM C-361 AWWA C-300 AWWA C-302 AWWA C-302 (f &=6OOO psi) (f ;=45OO psi)

AWWA C-301 1/

Concrete Volume cu yd I cu yd

AWWA C-301 not ordinarily available in diameters less than 42".

L#4@12. MAY USE &R $ D BUT NOT L E S S THAN 6

A1. C R A D L E

LBUT -NOT i~ LESS THAN A 2 CRADLE

6

TABLE J-E5 QUANTITY SURVEY CONDUIT CRADLE TYPE B1 BEDDING FOR CLASS (a) , (b) and ( c ) DAMS (per foot conduit length)

Conduit Inside Diameter

inch

Reinforcing Steel

I

lb

Type of Conduit ASTM C-7 6 I I ASTM C-361 AWWA C-300 AWWA C-301 AWWA C-302 AWWA C-302 11 Ei=6000 psi) (fl=4500 psi) ,cu yd

Concrete Volume 1 cu y d 1

cu yd

11 AWWA C-301 not ordinarily available in diameters less than 42". -

B1 BEDDING

TABLE J-E6 QUANTITY SURVEY ANTI-SEEP COLLARS TYPE A1 AND A2 CRADLES FOR DAMS CLASS (a) OVER 50 FEET HIGH AND CLASS (b) AND (c)

Type of C o n d u i t

Conduit Inside

Diameter

Teinf o r c i n g Steel

ASTM C-76 ] ASTM C-361 AWWA C-300 AWWA C-302 AWWA C-302 ( f :=6000 p s i ) (£:=4500 p s i )

I AWWA C-30:

Concrete Volume

inches

lb

cu. yd

cu yd

cu yd

*4@12 HORIZ *4@12 V E R T

-BOTTOM OF CRADLE

SECTION B - B

-49 I-

SECTION A-A

(SHOWING STEEL)

TABLE J-E7

QUANTITY SURVEY ANTI-SEEP COLLARS TYPE A 1 AND A2 CRADLES FOR DAMS CLASS (a) LESS THAN 50 FEET HIGH (per collar)

Conduit Inside Diameter

Reinforcing Steel

Type of Conduit ASTM C-76 AWWA C-300 ASTM C-361 ASTMC-302 AWWAC-302 (fh=6000 p s i ) (f ;=45OO p s i )

inch

lb

12 15 L6

54.45 59.2 60.5

1.055 1.139 1.151

18 20 21

62.5 63.7 65.55

1.195 1.242 1.270

cu yd

AWWA C-301

Concrete Volume cu- yd

cu yd

---

----

1.099

--

1.148 1.195

1.279

--

--

-.

27 30

67.55 76.0 77.5

1.333 1.413 1.492

1'. 356 1.439 1.523

33 36 42

80.45 81.95 86.1

1.569 1.655 1.878

1.610 1.692 1.847

1.627 1.784

2.008 2.160 2.343

2.038 2.218 2.390

1.952 2.239 2.325

24

48 54 60

99.4 110.0 118.2

1.321

--

1.471

--

3 @ 12 V E R T .

EICTTOM OF CRADLE

SECTION B-B

SECTION A-A (SHOWING STEEL)

TABLE J-E8 QUANTITY SURVEY ANTI-SEEP COLLARS TYPE R1 BEDDING FOR DAXS CLASS (a) OVER 50 FEET H I G H AND CLASS ( b ) AND ( c )

(per collar)

Type of C o n d u i t , Conduit Inside Dianeter

Reinforcing Steel

ASTM C-76 ASTM C-361 ASTM C-302 (fi=6000 p s i )

I

AIWA C-300 A W A C-302 (fr=4500 p s i )

AWWA C-301

.-

------cu yd

C o n c r e t e Volume cu yd

cu yd

TABLE J-E9 QUANTITY SURVEY ANTI-SEEP COLLARS TYPE B 1 BEDDING FOR DAMS CLASS (a) LESS THAN 50 FEET HIGH

(per collar)

Conduit Inside Diameter

--ylee

ASTM C-76

Of

Reinforcing Steel

ASTM C-302

A W A C-302

( f &=6000 psi) (f&=4500 p s i ) cu yd

TABLE J-F1 QUANTITY SURVEY PWD BASIN

Type o f P i p e . Welded S t e e l AWWA C-300 & CMP , AWWA ~ - 3 0 s l C o n c r e t e Voluqe c u yd cu v-d

.

Structure Size

A B

C

D

E

F

G

H

1/ -

Conduit Reinforcing S tee1 Inside Diameter inch lb 8 10 12 12 15 18

54 76 76 148 148 148

18 20 21 24 27

274 274 274 274 2 74

30 33 36 36 42 48 48 54 60 60 66 72

447 447 447 742 742 742 2364 2364 2364 3373 3373 3373

ASTM C-76 -AWWA C-302 cu yd

--

--

--

--

.99 1.94 1.93 1.92

--

--

-1.91

3.67

,

--

3.67 3.65

3.65 3.63 3.61

3.63

--

--

7.31

7.32 7.30 7.26 14.78 14.72 14.62 25.72 25.60 25.41 40.73 40.56 40.36

.

7.24 14.79 14.70 14.60 25.69 25.56 25.41 40.73 40.56 40.36

0.73 1.01 1.01 1.96 1.95 1.94 3.70 3.68 3.67 3.66 3.64 7.36 7.34 7.31 14.86 14.82 14.75 25.88 25.80 25.70 40.99 40.86 40.72

AWWA C-301 o r d i n a r i l y n o t a v a i l a b l e i n d i a m e t e r s l e s s t h a n 42".

I

TABLE J-F2 QUANTITY SURVEY IMPACT BASIN

Reinforcing Steel

ASTM C-76 AWWA C-302

*

Type o f Pipe AWWA C-300 AWWA C-301

Welded S t e e l & CMP

Concrete Vol.

cu yd

lb

cu yd

348 11 I 1

II

7

-

--

-

* **

Minimum wing w a l l l e n g t h .

Prestressed (AWWA C301) pipe only.

TABLE S-F2

Xructure Size

G

(continued)

ASTM C-76 AWWA C-302

Conduit Inside Diameter in.

Reinforcing Steel lb

cu yd

27 30 33 36 42 48 54

2944

23,72 23.65 23.57 23.49 23.29 23.07 22.83

11

11 II

II 1I It

Type o f P i p e AWWA C-300 AWWA C-301 C o n c r e t e Vol. cu yd

--

L

Welded S t e e l & CMP

I

cu yd